Semi-classical dynamics of superradiant Rayleigh scattering in a Bose-Einstein condensate

NASA Astrophysics Data System (ADS)

Müller, J. H.; Witthaut, D.; le Targat, R.; Arlt, J. J.; Polzik, E. S.; Hilliard, A. J.

2016-10-01

Due to its coherence properties and high optical depth, a Bose-Einstein condensate [BEC] provides an ideal setting to investigate collective atom-light interactions. Superradiant light scattering [SLS] in a BEC is a fascinating example of such an interaction. It is an analogous process to Dicke superradiance, in which an electronically inverted sample decays collectively, leading to the emission of one or more light pulses in a well-defined direction. Through time-resolved measurements of the superradiant light pulses emitted by an end-pumped BEC, we study the close connection of SLS with Dicke superradiance. A 1D model of the system yields good agreement with the experimental data and shows that the dynamics result from the structures that build up in the light and matter-wave fields along the BEC. This paves the way for exploiting the atom-photon correlations generated by the superradiance.

Strigolactones regulate rice tiller angle by attenuating shoot gravitropism through inhibiting auxin biosynthesis

PubMed Central

Sang, Dajun; Chen, Dongqin; Liu, Guifu; Liang, Yan; Huang, Linzhou; Meng, Xiangbing; Chu, Jinfang; Sun, Xiaohong; Dong, Guojun; Yuan, Yundong; Qian, Qian; Li, Jiayang; Wang, Yonghong

2014-01-01

Tiller angle, a key agronomic trait for achieving ideal plant architecture and increasing grain yield, is regulated mainly by shoot gravitropism. Strigolactones (SLs) are a group of newly identified plant hormones that are essential for shoot branching/rice tillering and have further biological functions as yet undetermined. Through screening for suppressors of lazy1 (sols), a classic rice mutant exhibiting large tiller angle and defective shoot gravitropism, we identified multiple SOLS that are involved in the SL biosynthetic or signaling pathway. We show that SL biosynthetic or signaling mutants can rescue the spreading phenotype of lazy1 (la1) and that SLs can inhibit auxin biosynthesis and attenuate rice shoot gravitropism, mainly by decreasing the local indoleacetic acid content. Although both SLs and LA1 are negative regulators of polar auxin transport, SLs do not alter the lateral auxin transport of shoot base, unlike LA1, which is a positive regulator of lateral auxin transport in rice. Genetic evidence demonstrates that SLs and LA1 participate in regulating shoot gravitropism and tiller angle in distinct genetic pathways. In addition, the SL-mediated shoot gravitropism is conserved in Arabidopsis. Our results disclose a new role of SLs and shed light on a previously unidentified mechanism underlying shoot gravitropism. Our study indicates that SLs could be considered as an important tool to achieve ideal plant architecture in the future. PMID:25028496

Strigolactones regulate rice tiller angle by attenuating shoot gravitropism through inhibiting auxin biosynthesis.

PubMed

Sang, Dajun; Chen, Dongqin; Liu, Guifu; Liang, Yan; Huang, Linzhou; Meng, Xiangbing; Chu, Jinfang; Sun, Xiaohong; Dong, Guojun; Yuan, Yundong; Qian, Qian; Li, Jiayang; Wang, Yonghong

2014-07-29

Tiller angle, a key agronomic trait for achieving ideal plant architecture and increasing grain yield, is regulated mainly by shoot gravitropism. Strigolactones (SLs) are a group of newly identified plant hormones that are essential for shoot branching/rice tillering and have further biological functions as yet undetermined. Through screening for suppressors of lazy1 (sols), a classic rice mutant exhibiting large tiller angle and defective shoot gravitropism, we identified multiple SOLS that are involved in the SL biosynthetic or signaling pathway. We show that SL biosynthetic or signaling mutants can rescue the spreading phenotype of lazy1 (la1) and that SLs can inhibit auxin biosynthesis and attenuate rice shoot gravitropism, mainly by decreasing the local indoleacetic acid content. Although both SLs and LA1 are negative regulators of polar auxin transport, SLs do not alter the lateral auxin transport of shoot base, unlike LA1, which is a positive regulator of lateral auxin transport in rice. Genetic evidence demonstrates that SLs and LA1 participate in regulating shoot gravitropism and tiller angle in distinct genetic pathways. In addition, the SL-mediated shoot gravitropism is conserved in Arabidopsis. Our results disclose a new role of SLs and shed light on a previously unidentified mechanism underlying shoot gravitropism. Our study indicates that SLs could be considered as an important tool to achieve ideal plant architecture in the future.

Adaptability test of lettuce to soil-like substrate in bioregenerative life support system

NASA Astrophysics Data System (ADS)

Min, Yan; Liu, Professor Hong; Wenting, Fu

Plant cultivation using soil-like substrate (SLS) is considered to be a feasible option for building up matter for biological turnover in bioregenerative life support system (BLSS) by many researchers. The characteristics of SLS are different from those of true soil therefore it is very important to study the adaptability of candidate crop to SLS in BLSS. This study was carried out in three successive steps to test the adaptability of lettuce (Lactuca sativa L.) to rice straw SLS in BLSS of China. First, six Chinese specific lettuce cultivars which were selected for Chinese advanced life support system were planted into the same rice straw SLS, which was to determine the more suitable plant cultivar to do the next experiment. The results showed that Sharp Leaf lettuce and Red lettuce were more suitable for SLS than other cultivars. Second, the possibility of increasing the crop yield on the SLS was conducted by changing the soil depth and plant density. Sharp Leaf lettuce and Red lettuce were used into this experiment in order to obtain the highest yield under the smallest soil volume and weight at the same light intensity. Crop edible biomass, crop nutrition content and photosynthetic characteristics were estimated during the experiment. Red lettuce obtained higher biomass and photosynthesis capacity. Lastly, the stability of planting system of lettuce and SLS was evaluated in the closed controlled system. Red lettuce would be the test plant. In this experiment different age lettuce groups would be planted together and gas exchange would be measured. In all of these experiments soil physical and chemical characteristics were also be measured which will be the basal data for further research.

Severe Life Stress and Oxidative Stress in the Brain: From Animal Models to Human Pathology

PubMed Central

Jaquet, Vincent; Trabace, Luigia; Krause, Karl-Heinz

2013-01-01

Abstract Significance: Severe life stress (SLS), as opposed to trivial everyday stress, is defined as a serious psychosocial event with the potential of causing an impacting psychological traumatism. Recent Advances: Numerous studies have attempted to understand how the central nervous system (CNS) responds to SLS. This response includes a variety of morphological and neurochemical modifications; among them, oxidative stress is almost invariably observed. Oxidative stress is defined as disequilibrium between oxidant generation and the antioxidant response. Critical Issues: In this review, we discuss how SLS leads to oxidative stress in the CNS, and how the latter impacts pathophysiological outcomes. We also critically discuss experimental methods that measure oxidative stress in the CNS. The review covers animal models and human observations. Animal models of SLS include sleep deprivation, maternal separation, and social isolation in rodents, and the establishment of hierarchy in non-human primates. In humans, SLS, which is caused by traumatic events such as child abuse, war, and divorce, is also accompanied by oxidative stress in the CNS. Future Directions: The outcome of SLS in humans ranges from resilience, over post-traumatic stress disorder, to development of chronic mental disorders. Defining the sources of oxidative stress in SLS might in the long run provide new therapeutic avenues. Antioxid. Redox Signal. 18, 1475–1490. PMID:22746161

SLS Payload Transportation Beyond LEO

NASA Technical Reports Server (NTRS)

Creech, S. D.; Baker, J. D.; Jackman, A. L.; Vane, G.

2017-01-01

NASA has successfully completed the Critical Design Review (CDR) of the heavy lift Space Launch System (SLS) and is working towards the first flight of the vehicle in 2018. SLS will begin flying crewed missions with an Orion capsule to the lunar vicinity every year after the first 2 flights starting in the early 2020's. As early as 2021, in addition to delivering an Orion capsule to a cislunar destination, SLS will also deliver ancillary payload, termed "Co-manifested Payload (CPL)", with a mass of at least 5.5 mT and volume up to 280 m3 simultaneously to that same destination. Later SLS flights have a goal of delivering as much as 10 mT of CPL to cislunar destinations. In addition to cislunar destinations, SLS flights may deliver non-crewed, science-driven missions with Primary Payload (PPL) to more distant destinations. SLS PPL missions will utilize a unique payload fairing offering payload volume (ranging from 320 m3 to 540 m3) that greatly exceeds the largest existing Expendable Launch Vehicle (ELV) fairing available. The Characteristic Energy (C3) offered by the SLS system will generate opportunities to deliver up to 40 mT to cislunar space, and deliver double PPL mass or de-crease flight time by half for some outer planet destinations when compared to existing capabilities. For example, SLS flights may deliver the Europa Clipper to a Jovian destination in under 3 years by the mid 2020's, compared to the 7+ years cruise time required for current launch capabilities. This presentation will describe ground and flight accommodations, interfaces, resources, and performance planned to be made available to potential CPL and PPL science users of SLS. In addition, this presentation should promote a dialogue between vehicle developers, potential payload users, and funding sources in order to most efficiently evolve required SLS capabilities to meet diverse payload needs as they are identified over the next 35 years and beyond.

X-ray Experiments for Students at the SLS Optics Beamline

NASA Astrophysics Data System (ADS)

Flechsig, U.; Als-Nielsen, J.; Jaggi, A.; Krempaský, J.; Oberta, P.; Spielmann, S.; van der Veen, J. F.

2010-06-01

We present a X-ray training course for students. The course covers fundamental properties of synchrotron radiation and basic techniques like scattering and absorption. We prepared ten experiments together with a tutorial. The whole course takes about a week. A first student group from the University of Copenhagen passed the course in June 2009. The experiments were performed at the optics beamline of the Swiss Light Source which can be part-time allocated for training purposes. Two experiments are described in more detail: scattering from a hanging drop of water turning into ice and measurement of the power of a pink synchrotron beam using a simple calorimeter.

Friction Stir Welding and NASA

NASA Technical Reports Server (NTRS)

Horton, K Renee

2016-01-01

Friction stir welding (FSW) is a solid state welding process with potential advantages for aerospace and automotive industries dealing with light alloys. Self-reacting friction stir welding (SR-FSW) is one variation of the FSW process being developed at the National Aeronautics and Space Administration (NASA) for use in the fabrication of propellant tanks and other areas used on the Space Launch System (SLS) NASA's SLS is an advanced, heavy-lift launch vehicle which will provide an entirely new capability for science and human exploration beyond Earth's orbit. The SLS will give the nation a safe, affordable and sustainable means of reaching beyond our current limits and open new doors of discovery from the unique vantage point of space This talk will elaborate on the SR-FSW process and it's usage on the current Space Launch System Program at NASA.

Semicontinuous sophorolipid fermentation using a novel bioreactor with dual ventilation pipes and dual sieve-plates coupled with a novel separation system.

PubMed

Zhang, Yaguang; Jia, Dan; Sun, Wanqi; Yang, Xue; Zhang, Chuanbo; Zhao, Fanglong; Lu, Wenyu

2018-05-01

Sophorolipids (SLs) are biosurfactants with widespread applications. The yield and purity of SLs are two important factors to be considered during their commercial large-scale production. Notably, SL accumulation causes an increase in viscosity, decrease in dissolved oxygen and product inhibition in the fermentation medium. This inhibits the further production and purification of SLs. This describes the development of a novel integrated system for SL production using Candida albicans O-13-1. Semicontinuous fermentation was performed using a novel bioreactor with dual ventilation pipes and dual sieve-plates (DVDSB). SLs were separated and recovered using a newly designed two-stage separation system. After SL recovery, the fermentation broth containing residual glucose and oleic acid was recycled back into the bioreactor. This novel approach considerably alleviated the problem of product inhibition and accelerated the rate of substrate utilization. Production of SLs achieved was 477 g l -1 , while their productivity was 1.59 g l -1  h -1 . Purity of SLs improved by 23.3%, from 60% to 74%, using DVDSB with the separation system. The conversion rate of carbon source increased from 0.5 g g -1 (in the batch fermentation) to 0.6 g g -1 . These results indicated that the integrated system could improve the efficiency of production and purity of SLs. © 2017 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

Overview of SLS Aeroacoustic Environment Development

NASA Technical Reports Server (NTRS)

Steva, Thomas; Herron, Andrew

2017-01-01

The Space Launch System (SLS) ascent aeroacoustic environments provide the externally driven noise levels predicted for vehicle ascent during transonic and supersonic flight, and serve as an important input for component and secondary structure vibroacoustic design criteria. This aerodynamically induced noise is predominantly generated by unsteady flow within the local boundary layer due to free stream interaction with the outer mold line (OML). Additional sources are shear flow interactions, shocks, protuberance flows, and wake flows. This presentation provides an overview of the aeroacoustics discipline along with the SLS environment development process, including wind tunnel testing and general data reduction methods. The state of the discipline is also presented with a summary of aeroacoustic measurement and computational techniques currently on the horizon.

Involvement of STH7 in light-adapted development in Arabidopsis thaliana promoted by both strigolactone and karrikin.

PubMed

Thussagunpanit, Jutiporn; Nagai, Yuko; Nagae, Miyu; Mashiguchi, Kiyoshi; Mitsuda, Nobutaka; Ohme-Takagi, Masaru; Nakano, Takeshi; Nakamura, Hidemitsu; Asami, Tadao

2017-02-01

Strigolactones (SLs) and karrikins (KARs) regulate photomorphogenesis. GR24, a synthetic SL and KAR 1 , a KAR, inhibit the hypocotyl elongation of Arabidopsis thaliana in a weak light. GR24 and KAR 1 up-regulate the expression of STH7, encoding a transcription factor belonging to the double B-box zinc finger subfamily. In this study, we used STH7-overexpressing (STH7ox) lines and functionally defective STH7 (STH7-SRDX) mutants to investigate roles of SLs and KARs in photomorphogenesis of Arabidopsis. Hypocotyl elongation of STH7-SRDX mutants was less sensitive to both GR24 and KAR 1 treatment than that of wild-type Arabidopsis under weak light conditions. Furthermore, the chlorophyll and anthocyanin content was increased in STH7ox lines when de-etiolated with light and GR24-treated plants had enhanced anthocyanin production. GR24 and KAR 1 treatment significantly increased the expression level of photosynthesis-related genes LHCB1 and rbcS. The results strongly suggest that SL and KAR induce photomorphogenesis of Arabidopsis in an STH7-dependent manner.

Strigolactones Inhibit Caulonema Elongation and Cell Division in the Moss Physcomitrella patens

PubMed Central

Hoffmann, Beate; Proust, Hélène; Belcram, Katia; Labrune, Cécile; Boyer, François-Didier; Rameau, Catherine; Bonhomme, Sandrine

2014-01-01

In vascular plants, strigolactones (SLs) are known for their hormonal role and for their role as signal molecules in the rhizosphere. SLs are also produced by the moss Physcomitrella patens, in which they act as signaling factors for controlling filament extension and possibly interaction with neighboring individuals. To gain a better understanding of SL action at the cellular level, we investigated the effect of exogenously added molecules (SLs or analogs) in moss growth media. We used the previously characterized Ppccd8 mutant that is deficient in SL synthesis and showed that SLs affect moss protonema extension by reducing caulonema cell elongation and mainly cell division rate, both in light and dark conditions. Based on this effect, we set up bioassays to examine chemical structure requirements for SL activity in moss. The results suggest that compounds GR24, GR5, and 5-deoxystrigol are active in moss (as in pea), while other analogs that are highly active in the control of pea branching show little activity in moss. Interestingly, the karrikinolide KAR1, which shares molecular features with SLs, did not have any effect on filament growth, even though the moss genome contains several genes homologous to KAI2 (encoding the KAR1 receptor) and no canonical homologue to D14 (encoding the SL receptor). Further studies should investigate whether SL signaling pathways have been conserved during land plant evolution. PMID:24911649

More Life-Science Experiments For Spacelab

NASA Technical Reports Server (NTRS)

Savage, P. D., Jr.; Dalton, B.; Hogan, R.; Leon, H.

1991-01-01

Report describes experiments done as part of Spacelab Life Sciences 2 mission (SLS-2). Research planned on cardiovascular, vestibular, metabolic, and thermal responses of animals in weightlessness. Expected to shed light on effects of prolonged weightlessness on humans.

STS-40 Spacelab Life Science 1 (SLS-1) module in OV-102's payload bay (PLB)

NASA Image and Video Library

1991-06-14

STS040-612-005 (5-14 June 1991) --- This view showing the Spacelab Life Sciences (SLS-1) module in Columbia's cargo bay was taken through windows on the aft flight deck. Under some lighting conditions the multi-layered Shuttle windows have internal reflections that provide a kaleidoscopic effect. In this image the sunrays as seen on the clouds also appear to be present in space. Note how the white sunlight toward the Sun at the Earth's limb becomes separated into the colors of the visible spectrum towards that part of the limb further into darkness due to atmosphere acting as a natural prism.

Enhancement of p-type conductivity by modifying the internal electric field in Mg- and Si-δ-codoped AlxGa1-xN/AlyGa1-yN superlattices

NASA Astrophysics Data System (ADS)

Li, Jinchai; Yang, Weihuang; Li, Shuping; Chen, Hangyang; Liu, Dayi; Kang, Junyong

2009-10-01

The internal electric field is modified by using Mg- and Si-δ-codoped AlxGa1-xN/AlyGa1-yN superlattices (SLs). The first-principles simulation results show that the internal electric field in SL has been significantly intensified due to the charge transferring from Si-doped interface to Mg-doped interface. Accordingly, the Mg- and Si-δ-codoped p-type Al0.2Ga0.8N/GaN SLs are grown by metalorganic vapor phase epitaxy and higher hole concentration as much as twice of that in modulation-doped SL has been achieved, as determined by Hall effect measurements. Furthermore, by applying Mg- and Si-δ-codoped AlxGa1-xN/AlyGa1-yN SLs with high Al content as the p-type layers, we have fabricated deep ultraviolet light emitting diodes with superior current-voltage characteristics by lowering Mg-acceptor activation energy.

Physcomitrella patens MAX2 characterization suggests an ancient role for this F-box protein in photomorphogenesis rather than strigolactone signalling.

PubMed

Lopez-Obando, Mauricio; de Villiers, Ruan; Hoffmann, Beate; Ma, Linnan; de Saint Germain, Alexandre; Kossmann, Jens; Coudert, Yoan; Harrison, C Jill; Rameau, Catherine; Hills, Paul; Bonhomme, Sandrine

2018-05-21

Strigolactones (SLs) are key hormonal regulators of flowering plant development and are widely distributed amongst streptophytes. In Arabidopsis, SLs signal via the F-box protein MORE AXILLARY GROWTH2 (MAX2), affecting multiple aspects of development including shoot branching, root architecture and drought tolerance. Previous characterization of a Physcomitrella patens moss mutant with defective SL synthesis supports an ancient role for SLs in land plants, but the origin and evolution of signalling pathway components are unknown. Here we investigate the function of a moss homologue of MAX2, PpMAX2, and characterize its role in SL signalling pathway evolution by genetic analysis. We report that the moss Ppmax2 mutant shows very distinct phenotypes from the moss SL-deficient mutant. In addition, the Ppmax2 mutant remains sensitive to SLs, showing a clear transcriptional SL response in dark conditions, and the response to red light is also altered. These data suggest divergent evolutionary trajectories for SL signalling pathway evolution in mosses and vascular plants. In P. patens, the primary roles for MAX2 are in photomorphogenesis and moss early development rather than in SL response, which may require other, as yet unidentified, factors. © 2018 INRA New Phytologist © 2018 New Phytologist Trust.

In 0.35Ga 0.65P light-emitting diodes grown by gas-source MBE

NASA Astrophysics Data System (ADS)

Masselink, W. Ted; Zachau, Martin

1993-02-01

This paper describes the growth and optical characteristics of In yGa 1- yP with 0.3< y<0.5, and the LED operation of p-i-n structures in the same materials system. The InGaP is grown using gas-source molecular beam epitaxy (GSMBE). The non-lattice-matched In yGa 1- yP grown on GaAs using GSMBE has a specularly smooth surface morphology through the use of unique strained-layer superlattice (SLS) buffer. We have measured the luminescence, luminescence excitation, and Raman spectra of these undoped films and observe strong excitonic luminescence over the entire composition range investigated. The band gap derived from the luminescence excitation spectra corresponds to that of a fully relaxed InGaP film with no residual strain, which is confirmed by the Raman measurements. Light-emitting diodes with peak (300 K) emission centered at less than 590 nm have been fabricated from p-i-n junctions in In 0.35Ga 0.65P. This alloy is close to that with the largest direct band gap in the In yGa 1- y P system and has lattice mismatch from the GaAs substrate of 1%.

Effect of sodium lauryl sulfate on recurrent aphthous stomatitis: a randomized controlled clinical trial.

PubMed

Shim, Y J; Choi, J-H; Ahn, H-J; Kwon, J-S

2012-10-01

To compare the effects of sodium lauryl sulfate (SLS)-free and SLS-containing dentifrice in patient with recurrent aphthous stomatitis (RAS). The design of this study was a double-blind crossover trial. The 90 subjects were divided into three groups: group I used SLS-free (a commercially available SLS-free dentifrice) and SLS-A (SLS-free + 1.5% SLS), group II used SLS-A and SLS-B (a commercially available 1.5% SLS-containing dentifrice), and group III used SLS-free and SLS-B. The subjects used one of the two assigned dentifrices for 8 weeks and then the other for the following 8 weeks. The order of the dentifrices used was selected at random, and there was a 2-week washout period between the two phases. The clinical parameters (number of ulcers, number of episodes, duration of ulcers, mean pain score) were compared between the two phases for each group. The number of ulcers and episodes did not differ significantly between SLS-A, SLS-B, and SLS-free. Only duration of ulcers and mean pain score was significantly decreased during the period using SLS-free. Although SLS-free did not reduce the number of ulcers and episodes, it affected the ulcer-healing process and reduces pain in daily lives in patients with RAS. © 2012 John Wiley & Sons A/S.

Fuel From Algae: Scaling and Commercialization of Algae Harvesting Technologies

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

2010-01-15

Broad Funding Opportunity Announcement Project: Led by CEO Ross Youngs, AVS has patented a cost-effective dewatering technology that separates micro-solids (algae) from water. Separating micro-solids from water traditionally requires a centrifuge, which uses significant energy to spin the water mass and force materials of different densities to separate from one another. In a comparative analysis, dewatering 1 ton of algae in a centrifuge costs around $3,400. AVS’s Solid-Liquid Separation (SLS) system is less energy-intensive and less expensive, costing $1.92 to process 1 ton of algae. The SLS technology uses capillary dewatering with filter media to gently facilitate water separation, leavingmore » behind dewatered algae which can then be used as a source for biofuels and bio-products. The biomimicry of the SLS technology emulates the way plants absorb and spread water to their capillaries.« less

Whistle source levels of free-ranging beluga whales in Saguenay-St. Lawrence marine park.

PubMed

Le Bot, Olivier; Simard, Yvan; Roy, Nathalie; Mars, Jérôme I; Gervaise, Cédric

2016-07-01

Wild beluga whistle source levels (SLs) are estimated from 52 three-dimensional (3D) localized calls using a 4-hydrophone array. The probability distribution functions of the root-mean-square (rms) SL in the time domain, and the peak, the strongest 3-dB, and 10-dB SLs from the spectrogram, were non-Gaussian. The average rms SL was 143.8 ± 6.7 dB re 1 μPa at 1 m. SL spectral metrics were, respectively, 145.8 ± 8 dB, 143.2 ± 7.1 dB, and 138.5 ± 6.9 dB re 1 μPa(2)·Hz(-1) at 1 m.

Methyl phenlactonoates are efficient strigolactone analogs with simple structure

PubMed Central

Jamil, Muhammad; Kountche, Boubacar A; Haider, Imran; Guo, Xiujie; Ntui, Valentine O; Jia, Kun-Peng; Hameed, Umar S; Nakamura, Hidemitsu; Lyu, Ying; Jiang, Kai; Hirabayashi, Kei; Tanokura, Masaru; Arold, Stefan T; Asami, Tadao

2018-01-01

abstract Strigolactones (SLs) are a new class of phytohormones that also act as germination stimulants for root parasitic plants, such as Striga spp., and as branching factors for symbiotic arbuscular mycorrhizal fungi. Sources for natural SLs are very limited. Hence, efficient and simple SL analogs are needed for elucidating SL-related biological processes as well as for agricultural applications. Based on the structure of the non-canonical SL methyl carlactonoate, we developed a new, easy to synthesize series of analogs, termed methyl phenlactonoates (MPs), evaluated their efficacy in exerting different SL functions, and determined their affinity for SL receptors from rice and Striga hermonthica. Most of the MPs showed considerable activity in regulating plant architecture, triggering leaf senescence, and inducing parasitic seed germination. Moreover, some MPs outperformed GR24, a widely used SL analog with a complex structure, in exerting particular SL functions, such as modulating Arabidopsis roots architecture and inhibiting rice tillering. Thus, MPs will help in elucidating the functions of SLs and are promising candidates for agricultural applications. Moreover, MPs demonstrate that slight structural modifications clearly impact the efficiency in exerting particular SL functions, indicating that structural diversity of natural SLs may mirror a functional specificity. PMID:29300919

Evolution of Structural and Optical Properties of ZnO Nanorods Grown on Vacuum Annealed Seed Crystallites

PubMed Central

Khan, Fasihullah; Ajmal, Hafiz Muhammad Salman; Huda, Noor Ul; Kim, Ji Hyun; Kim, Sam-Dong

2018-01-01

In this study, the ambient condition for the as-coated seed layer (SL) annealing at 350 °C is varied from air or nitrogen to vacuum to examine the evolution of structural and optical properties of ZnO nanorods (NRs). The NR crystals of high surface density (~240 rods/μm2) and aspect ratio (~20.3) show greatly enhanced (002) degree of orientation and crystalline quality, when grown on the SLs annealed in vacuum, compared to those annealed in air or nitrogen ambient. This is due to the vacuum-annealed SL crystals of a highly preferred orientation toward (002) and large grain sizes. X-ray photoelectron spectroscopy also reveals that the highest O/Zn atomic ratio of 0.89 is obtained in the case of vacuum-annealed SL crystals, which is due to the effective desorption of hydroxyl groups and other contaminants adsorbed on the surface formed during aqueous solution-based growth process. Near band edge emission (ultra violet range of 360–400 nm) of the vacuum-annealed SLs is also enhanced by 44% and 33% as compared to those annealed in air and nitrogen ambient, respectively, in photoluminescence with significant suppression of visible light emission associated with deep level transition. Due to this improvement of SL optical crystalline quality, the NR crystals grown on the vacuum-annealed SLs produce ~3 times higher ultra violet emission intensity than the other samples. In summary, it is shown that the ZnO NRs preferentially grow along the wurtzite c-axis direction, thereby producing the high crystalline quality of nanostructures when they grow on the vacuum-annealed SLs of high crystalline quality with minimized impurities and excellent preferred orientation. The ZnO nanostructures of high crystalline quality achieved in this study can be utilized for a wide range of potential device applications such as laser diodes, light-emitting diodes, piezoelectric transducers and generators, gas sensors, and ultraviolet detectors. PMID:29373523

Effects of multiple scattering on radiative properties of soot fractal aggregates

NASA Astrophysics Data System (ADS)

Yon, Jérôme; Liu, Fengshan; Bescond, Alexandre; Caumont-Prim, Chloé; Rozé, Claude; Ouf, François-Xavier; Coppalle, Alexis

2014-01-01

The in situ optical characterization of smokes composed of soot particles relies on light extinction, angular static light scattering (SLS), or laser induced incandescence (LII). These measurements are usually interpreted by using the Rayleigh-Debye-Gans theory for Fractal Aggregates (RDG-FA). RDG-FA is simple to use but it completely neglects the impact of multiple scattering (MS) within soot aggregates. In this paper, based on a scaling approach that takes into account MS effects, an extended form of the RDG-FA theory is proposed in order to take into account these effects. The parameters of this extended theory and their dependency on the number of primary sphere inside the aggregate (1

Voltage tunable two-color superlattice infrared photodetectors

NASA Astrophysics Data System (ADS)

Majumdar, Amlan; Choi, Kwong-Kit; Reno, John L.; Tsui, Daniel C.

2004-11-01

We present the design and fabrication of voltage tunable two-color superlattice infrared photodetectors (SLIPs), where the detection wavelength switches from the long-wavelength infrared (LWIR) range to the mid-wavelength infrared (MWIR) range upon reversing the polarity of applied bias. The photoactive region of these detectors contains multiple periods of two distinct short-period SLs that are designed for MWIR and LWIR detection. The voltage tunable operation is achieved by using two types of thick blocking barriers between adjacent SLs - undoped barriers on one side for low energy electrons and heavily-doped layers on the other side for high energy electrons. We grew two SLIP structures by molecular beam epitaxy. The first one consists of two AlGaAs/GaAs SLs with the detection range switching from the 7-11 μm band to the 4-7 μm range on reversing the bias polarity. The background-limited temperature is 55 and 80 K for LWIR and MWIR detection, respectively. The second structure comprises of strained InGaAs/GaAs/AlGaAs SLs and AlGaAs/GaAs SLs. The detection range of this SLIP changes from the 8-12 μm band to the 3-5 μm band on switching the bias polarity. The background-limited temperature is 70 and 110 K for LWIR and MWIR detection, respectively. This SLIP is the first ever voltage tunable MWIR/LWIR detector with performance comparable to those of one-color quantum-well infrared detectors designed for the respective wavelength ranges. We also demonstrate that the corrugated light coupling scheme, which enables normal-incidence absorption, is suitable for the two-color SLIPs. Since these SLIPs are two-terminal devices, they can be used with the corrugated geometry for the production of low-cost large-area two-color focal plane arrays.

Fast two-dimensional grid and transmission X-ray microscopy scanning methods for visualizing and characterizing protein crystals

PubMed Central

Wojdyla, Justyna Aleksandra; Panepucci, Ezequiel; Martiel, Isabelle; Ebner, Simon; Huang, Chia-Ying; Caffrey, Martin; Bunk, Oliver; Wang, Meitian

2016-01-01

A fast continuous grid scan protocol has been incorporated into the Swiss Light Source (SLS) data acquisition and analysis software suite on the macromolecular crystallography (MX) beamlines. Its combination with fast readout single-photon counting hybrid pixel array detectors (PILATUS and EIGER) allows for diffraction-based identification of crystal diffraction hotspots and the location and centering of membrane protein microcrystals in the lipid cubic phase (LCP) in in meso in situ serial crystallography plates and silicon nitride supports. Diffraction-based continuous grid scans with both still and oscillation images are supported. Examples that include a grid scan of a large (50 nl) LCP bolus and analysis of the resulting diffraction images are presented. Scanning transmission X-ray microscopy (STXM) complements and benefits from fast grid scanning. STXM has been demonstrated at the SLS beamline X06SA for near-zero-dose detection of protein crystals mounted on different types of sample supports at room and cryogenic temperatures. Flash-cooled crystals in nylon loops were successfully identified in differential and integrated phase images. Crystals of just 10 µm thickness were visible in integrated phase images using data collected with the EIGER detector. STXM offers a truly low-dose method for locating crystals on solid supports prior to diffraction data collection at both synchrotron microfocusing and free-electron laser X-ray facilities. PMID:27275141

NOT ALL SINGLE LEG SQUATS ARE EQUAL: A BIOMECHANICAL COMPARISON OF THREE VARIATIONS.

PubMed

Khuu, Anne; Foch, Eric; Lewis, Cara L

2016-04-01

The single leg squat (SLS) is a functional task used by practitioners to evaluate and treat multiple pathologies of the lower extremity. Variations of the SLS may have different neuromuscular and biomechanical demands. The effect of altering the non-stance leg position during the SLS on trunk, pelvic, and lower extremity mechanics has not been reported. The purpose of this study was to compare trunk, pelvic, hip, knee, and ankle kinematics and hip, knee, and ankle kinetics of three variations of the SLS using different non-stance leg positions: SLS-Front, SLS-Middle, and SLS-Back. Sixteen healthy women performed the three SLS tasks while data were collected using a motion capture system and force plates. Joint mechanics in the sagittal, frontal, and transverse planes were compared for the SLS tasks using a separate repeated-measures analysis of variance (ANOVA) for each variable at two analysis points: peak knee flexion (PKF) and 60 ° of knee flexion (60KF). Different non-stance leg positions during the SLS resulted in distinct movement patterns and moments at the trunk, pelvis, and lower extremity. At PKF, SLS-Back exhibited the greatest kinematic differences (p < 0.05) from SLS-Front and SLS-Middle with greater ipsilateral trunk flexion, pelvic anterior tilt and drop, hip flexion and adduction, and external rotation as well as less knee flexion and abduction. SLS-Back also showed the greatest kinetic differences (p < 0.05) from SLS-Front and SLS-Middle with greater hip external rotator moment and knee extensor moment as well as less hip extensor moment and knee adductor moment at PKF. At 60KF, the findings were similar except at the knee. The mechanics of the trunk, pelvis, and lower extremity during the SLS were affected by the position of the non-stance leg in healthy females. Practitioners can use these findings to distinguish between SLS variations and to select the appropriate SLS for assessment and rehabilitation. 3.

[Testing reliability and validity of reduced substitutes for leadership scales(rd-SLS)].

PubMed

Kim, Jeong-Hee

2005-10-01

This paper was conducted to test the reliability and validity of rd-SLS, developed by Podsakoff, et al. (1993) which measured 'substitutes for leadership'. The subjects were 345 nurses in 5 general hospitals. Cronbach's and the Guttman split-half coefficient were used to test the reliability of rd-SLS. Factor analysis, and the correlations of the rv-SLS and SLS with rd-SLS were used for convergent and discriminant validity. Cronbach's data was 0.76 and the Guttman split-half coefficient was 0.52. Twelve factors evolved by factor analysis, which explained 70.4% of the total variance. This result was similar to previous study results. However, 'Indifference toward organizational rewards'-related items were classified two factors. It was not clear t hat the rd-SLS consisted of 13 concepts(factors). The correlations of the rv-SLS and SLS with the rd-SLS were 0.93 and 0.87 respectively. The rd-SLS showed a moderate degree of validity and reliability. Thus, it is recommended to use the rd-SLS in general nursing organizations for screening for leadership substitutes. In addition, it is necessary to clarify the concept of organizational rewards. In a further study, the factor structure of the rd-SLS may be considered.

Strigolactone regulation of shoot branching in chrysanthemum (Dendranthema grandiflorum)

PubMed Central

Liang, Jianli; Zhao, Liangjun; Challis, Richard; Leyser, Ottoline

2010-01-01

Previous studies of highly branched mutants in pea (rms1–rms5), Arabidopsis thaliana (max1–max4), petunia (dad1–dad3), and rice (d3, d10, htd1/d17, d14, d27) identified strigolactones or their derivates (SLs), as shoot branching inhibitors. This recent discovery offers the possibility of using SLs to regulate branching commercially, for example, in chrysanthemum, an important cut flower crop. To investigate this option, SL physiology and molecular biology were studied in chrysanthemum (Dendranthema grandiflorum), focusing on the CCD8/MAX4/DAD1/RMS1/D10 gene. Our results suggest that, as has been proposed for Arabidopsis, the ability of SLs to inhibit bud activity depends on the presence of a competing auxin source. The chrysanthemum SL biosynthesis gene, CCD8 was cloned, and found to be regulated in a similar, but not identical way to known CCD8s. Expression analyses revealed that DgCCD8 is predominantly expressed in roots and stems, and is up-regulated by exogenous auxin. Exogenous SL can down-regulate DgCCD8 expression, but this effect can be overridden by apical auxin application. This study provides evidence that SLs are promising candidates to alter the shoot branching habit of chrysanthemum. PMID:20478970

Light comfort zones of mesopelagic acoustic scattering layers in two contrasting optical environments

NASA Astrophysics Data System (ADS)

Røstad, Anders; Kaartvedt, Stein; Aksnes, Dag L.

2016-07-01

We make a comparison of the mesopelagic sound scattering layers (SLs) in two contrasting optical environments; the clear Red Sea and in murkier coastal waters of Norway (Masfjorden). The depth distributions of the SL in Masfjorden are shallower and narrower than those of the Red Sea. This difference in depth distribution is consistent with the hypothesis that the organisms of the SL distribute according to similar light comfort zones (LCZ) in the two environments. Our study suggest that surface and underwater light measurements ranging more than 10 orders of magnitude is required to assess the controlling effects of light on SL structure and dynamics.

Human insulin polymorphism upon ligand binding and pH variation: the case of 4-ethylresorcinol.

PubMed

Fili, S; Valmas, A; Norrman, M; Schluckebier, G; Beckers, D; Degen, T; Wright, J; Fitch, A; Gozzo, F; Giannopoulou, A E; Karavassili, F; Margiolaki, I

2015-09-01

This study focuses on the effects of the organic ligand 4-ethylresorcinol on the crystal structure of human insulin using powder X-ray crystallography. For this purpose, systematic crystallization experiments have been conducted in the presence of the organic ligand and zinc ions within the pH range 4.50-8.20, while observing crystallization behaviour around the isoelectric point of insulin. High-throughput crystal screening was performed using a laboratory X-ray diffraction system. The most representative samples were selected for synchrotron X-ray diffraction measurements, which took place at the European Synchrotron Radiation Facility (ESRF) and the Swiss Light Source (SLS). Four different crystalline polymorphs have been identified. Among these, two new phases with monoclinic symmetry have been found, which are targets for the future development of microcrystalline insulin drugs.

Human insulin polymorphism upon ligand binding and pH variation: the case of 4-ethylresorcinol

PubMed Central

Fili, S.; Valmas, A.; Norrman, M.; Schluckebier, G.; Beckers, D.; Degen, T.; Wright, J.; Fitch, A.; Gozzo, F.; Giannopoulou, A. E.; Karavassili, F.; Margiolaki, I.

2015-01-01

This study focuses on the effects of the organic ligand 4-ethylresorcinol on the crystal structure of human insulin using powder X-ray crystallography. For this purpose, systematic crystallization experiments have been conducted in the presence of the organic ligand and zinc ions within the pH range 4.50–8.20, while observing crystallization behaviour around the isoelectric point of insulin. High-throughput crystal screening was performed using a laboratory X-ray diffraction system. The most representative samples were selected for synchrotron X-ray diffraction measurements, which took place at the European Synchrotron Radiation Facility (ESRF) and the Swiss Light Source (SLS). Four different crystalline polymorphs have been identified. Among these, two new phases with monoclinic symmetry have been found, which are targets for the future development of microcrystalline insulin drugs. PMID:26306195

Defect imaging for plate-like structures using diffuse field.

PubMed

Hayashi, Takahiro

2018-04-01

Defect imaging utilizing a scanning laser source (SLS) technique produces images of defects in a plate-like structure, as well as spurious images occurring because of resonances and reverberations within the specimen. This study developed defect imaging by the SLS using diffuse field concepts to reduce the intensity of spurious images, by which the energy of flexural waves excited by laser can be estimated. The experimental results in the different frequency bandwidths of excitation waves and in specimens with different attenuation proved that clearer images of defects are obtained in broadband excitation using a chirp wave and in specimens with low attenuation, which produce diffuse fields easily.

First Light Detected from Gravitational Wave Event on This Week @NASA – October 20, 2017

NASA Image and Video Library

2017-10-20

For the first time, NASA scientists have detected light tied to a gravitational-wave event. The gravitational wave – caused by an explosive merger of two neutron stars, about 130 million light-years from Earth – produced a gamma-ray burst and a rarely seen flare-up called a "kilonova". The phenomenon was captured by our Fermi, Swift, Hubble, Chandra and Spitzer missions, along with dozens of NASA-funded ground-based observatories. Also, Trio of Station Spacewalks Completed, Fresh Findings from Cassini, and Test of SLS RS-25 Flight Engine!

Rhodamine-123: a p-glycoprotein marker complex with sodium lauryl sulfate.

PubMed

Al-Mohizea, Abdullah M; Al-Jenoobi, Fahad Ibrahim; Alam, Mohd Aftab

2015-03-01

Aim of this study was to investigate the role of sodium lauryl sulfate (SLS) as P-glycoprotein inhibitor. The everted rat gut sac model was used to study in-vitro mucosal to serosal transport of Rhodamine-123 (Rho-123). Surprisingly, SLS decreases the serosal absorption of Rho-123 at all investigated concentrations. Investigation reveals complex formation between Rhodamine-123 and sodium lauryl sulfate. Interaction profile of SLS & Rho-123 was studied at variable SLS concentrations. The SLS concentration higher than critical micelle concentration (CMC) increases the solubility of Rho-123 but could not help in serosal absorption, on the contrary the absorption of Rho-123 decreased. Rho-123 and SLS form pink color complex at sub-CMC. The SLS concentrations below CMC decrease the solubility of Rho-123. For further studies, Rho-123 & SLS complex was prepared by using solvent evaporation technique and characterized by using differential scanning calorimeter (DSC). Thermal analysis also proved the formation of complex between SLS & Rho-123. The P values were found to be significant (<0.05) except group comprising 0.0001% SLS, and that is because 0.0001% SLS is seems to be very low to affect the solubility or complexation of Rho-123.

Strigolactones Effects on Root Growth

NASA Astrophysics Data System (ADS)

Koltai, Hinanit

2012-07-01

Strigolactones (SLs) were defined as a new group of plant hormones that suppress lateral shoot branching. Our previous studies suggested SLs to be regulators of root development. SLs were shown to alter root architecture by regulating lateral root formation and to affect root hair elongation in Arabidopsis. Another important effect of SLs on root growth was shown to be associated with root directional growth. Supplementation of SLs to roots led to alterations in root directional growth, whereas associated mutants showed asymmetrical root growth, which was influenced by environmental factors. The regulation by SLs of root development was shown to be conducted via a cross talk of SLs with other plant hormones, including auxin. SLs were shown to regulate auxin transport, and to interfere with the activity of auxin-efflux carriers. Therefore, it might be that SLs are regulators of root directional growth as a result of their ability to regulated auxin transport. However, other evidences suggest a localized effect of SLs on cell division, which may not necessarily be associated with auxin efflux. These and other, recent hypothesis as to the SLs mode of action and the associated root perception and response to environmental factors will be discussed.

6DOF Testing of the SLS Inertial Navigation Unit

NASA Technical Reports Server (NTRS)

Geohagan, Kevin; Bernard, Bill; Oliver, T. Emerson; Leggett, Jared; Strickland, Dennis

2018-01-01

The Navigation System on the NASA Space Launch System (SLS) Block 1 vehicle performs initial alignment of the Inertial Navigation System (INS) navigation frame through gyrocompass alignment (GCA). Because the navigation architecture for the SLS Block 1 vehicle is a purely inertial system, the accuracy of the achieved orbit relative to mission requirements is very sensitive to initial alignment accuracy. The assessment of this sensitivity and many others via simulation is a part of the SLS Model-Based Design and Model-Based Requirements approach. As a part of the aforementioned, 6DOF Monte Carlo simulation is used in large part to develop and demonstrate verification of program requirements. To facilitate this and the GN&C flight software design process, an SLS-Program-controlled Design Math Model (DMM) of the SLS INS was developed by the SLS Navigation Team. The SLS INS model implements all of the key functions of the hardware-namely, GCA, inertial navigation, and FDIR (Fault Detection, Isolation, and Recovery)-in support of SLS GN&C design requirements verification. Despite the strong sensitivity to initial alignment, GCA accuracy requirements were not verified by test due to program cost and schedule constraints. Instead, the system relies upon assessments performed using the SLS INS model. In order to verify SLS program requirements by analysis, the SLS INS model is verified and validated against flight hardware. In lieu of direct testing of GCA accuracy in support of requirement verification, the SLS Navigation Team proposed and conducted an engineering test to, among other things, validate the GCA performance and overall behavior of the SLS INS model through comparison with test data. This paper will detail dynamic hardware testing of the SLS INS, conducted by the SLS Navigation Team at Marshall Space Flight Center's 6DOF Table Facility, in support of GCA performance characterization and INS model validation. A 6-DOF motion platform was used to produce 6DOF pad twist and sway dynamics while a simulated SLS flight computer communicated with the INS. Tests conducted include an evaluation of GCA algorithm robustness to increasingly dynamic pad environments, an examination of GCA algorithm stability and accuracy over long durations, and a long-duration static test to gather enough data for Allan Variance analysis. Test setup, execution, and data analysis will be discussed, including analysis performed in support of SLS INS model validation.

Space Launch System (SLS) Mission Planner's Guide

NASA Technical Reports Server (NTRS)

Smith, David Alan

2017-01-01

The purpose of this Space Launch System (SLS) Mission Planner's Guide (MPG) is to provide future payload developers/users with sufficient insight to support preliminary SLS mission planning. Consequently, this SLS MPG is not intended to be a payload requirements document; rather, it organizes and details SLS interfaces/accommodations in a manner similar to that of current Expendable Launch Vehicle (ELV) user guides to support early feasibility assessment. Like ELV Programs, once approved to fly on SLS, specific payload requirements will be defined in unique documentation.

In vivo and in vitro analysis of low level light therapy: a useful therapeutic approach for sensitive skin.

PubMed

Choi, M; Kim, J E; Cho, K H; Lee, J H

2013-11-01

Sensitive skin is a relatively common dermatologic condition and no optimal treatments have been established so far. Low-level laser/light therapy (LLLT) has been used for its biostimulative effect in various clinical settings. The purpose of this study was to investigate whether low-level laser/light therapy can improve sensitive skin clinically and to evaluate the effects of LLLT on skin in vitro. Twenty-eight patients complaining of sensitive skin were treated with low-level polarized light, and clinical results were evaluated using subjective and objective method. To investigate possible working mechanism of LLLT on skin, cultured human keratinocytes pretreated with nontoxic concentration of sodium lauryl sulfate (SLS) were used. Cytokines released from irritated keratinocytes after LLLT were analyzed. All patients showed subjective and objective improvement after treatment. No adverse effects were reported. The average number of LLLT sessions required to achieve clinical improvement was 9.9, and cumulative dose of LLLT was 71.3 J/cm(2) on the average. Erythema index decreased significantly after LLLT treatment (p = 0.017). In vitro assay showed that LLLT significantly reduced the release of VEGF from SLS-pretreated keratinocytes (p = 0.021). Our results suggest that LLLT could be a useful and safe treatment modality for sensitive skin, and modification of inflammatory cytokines released from irritated keratinocytes may be considered as one of plausible mechanisms in sensitive skin treated with LLLT.

Oral fluoride levels 1 h after use of a sodium fluoride rinse: effect of sodium lauryl sulfate.

PubMed

Vogel, Gerald L; Schumacher, Gary E; Chow, Laurence C; Tenuta, Livia M A

2015-01-01

Increasing the concentration of free fluoride in oral fluids is an important goal in the use of topical fluoride agents. Although sodium lauryl sulfate (SLS) is a common dentifrice ingredient, the influence of this ion on plaque fluid and salivary fluid fluoride has not been examined. The purpose of this study was to investigate the effect of SLS on these parameters and to examine the effect of this ion on total (or whole) plaque fluoride, an important source of plaque fluid fluoride after a sufficient interval following fluoride administration, and on total salivary fluoride, a parameter often used as a surrogate measure of salivary fluid fluoride. Ten subjects accumulated plaque for 48 h before rinsing with a 12 mmol/l NaF (228 µg/g F) rinse containing or not containing 0.5% (w/w) SLS. SLS had no statistically significant effect on total plaque and total saliva fluoride but significantly increased salivary fluid and plaque fluid fluoride (by 147 and 205%, respectively). These results suggest that the nonfluoride components of topical agents can be manipulated to improve the fluoride release characteristics from oral fluoride reservoirs and that statistically significant change may be observed in plaque fluid and salivary fluid fluoride concentrations that may not be observed in total plaque and total saliva fluoride concentrations.

Instrumentation on Multi-Scaled Scattering of Bio-Macromolecular Solutions

PubMed Central

Chu, Benjamin; Fang, Dufei; Mao, Yimin

2015-01-01

The design, construction and initial tests on a combined laser light scattering and synchrotron X-ray scattering instrument can cover studies of length scales from atomic sizes in Angstroms to microns and dynamics from microseconds to seconds are presented. In addition to static light scattering (SLS), dynamic light scattering (DLS), small angle X-ray scattering (SAXS) and wide angle X-ray diffraction (WAXD), the light scattering instrument is being developed to carry out studies in mildly turbid solutions, in the presence of multiple scattering. Three-dimensional photon cross correlation function (3D-PCCF) measurements have been introduced to couple with synchrotron X-ray scattering to study the structure, size and dynamics of macromolecules in solution. PMID:25946340

Growth of plant tissue cultures in simulated lunar soil: Implications for a lunar base CELSS (Controlled Ecological Life Support System)

NASA Technical Reports Server (NTRS)

Venketeswaran, S.

1988-01-01

Experiments were carried out on plant tissue cultures, seed germination, seedling development and plants grown on Simulated Lunar Soil to evaluate the potential of future development of lunar based agriculture. The studies done to determine the effect of the placement of SLS on tissue cultures showed no adverse effect of SLS on tissue cultures. Although statistically insignificant, SLS in suspension showed a comparatively higher growth rate. Observations indicate the SLS, itself cannot support calli growth but was able to show a positive effect on growth rate of calli when supplemented with MS salts. This positive effect related to nutritive value of the SLS was found to have improved at high pH levels, than at the recommended low pH levels for standard media. Results from seed germination indicated that there is neither inhibitory, toxicity nor stimulatory effect of SLS, even though SLS contains high amounts of aluminum compounds compared to earth soil. Analysis of seeding development and growth data showed significant reduction in growth rate indicating that, SLS was a poor growth medium for plant life. This was confirmed by the studies done with embryos and direct plant growth on SLS. Further observations attributed this poor quality of SLS is due to it's lack of essential mineral elements needed for plant growth. By changing the pH of the soil, to more basic conditions, the quality of SLS for plant growth could be improved up to a significant level. Also it was found that the quality of SLS could be improved by almost twice, by external supply of major mineral elements, directly to SLS.

NASA Space Launch System (SLS) Progress Report

NASA Technical Reports Server (NTRS)

Williams, Tom

2012-01-01

The briefing objectives are: (1) Explain the SLS current baseline architecture and the SLS block-upgrade approach. (2) Summarize the SLS evolutionary path in relation to the Advanced Booster and Advanced Development NASA Research Announcements.

Time and Frequency-Domain Cross-Verification of SLS 6DOF Trajectory Simulations

NASA Technical Reports Server (NTRS)

Johnson, Matthew; McCullough, John

2017-01-01

The Space Launch System (SLS) Guidance, Navigation, and Control (GNC) team and its partners have developed several time- and frequency-based simulations for development and analysis of the proposed SLS launch vehicle. The simulations differ in fidelity and some have unique functionality that allows them to perform specific analyses. Some examples of the purposes of the various models are: trajectory simulation, multi-body separation, Monte Carlo, hardware in the loop, loads, and frequency domain stability analyses. While no two simulations are identical, many of the models are essentially six degree-of-freedom (6DOF) representations of the SLS plant dynamics, hardware implementation, and flight software. Thus at a high level all of those models should be in agreement. Comparison of outputs from several SLS trajectory and stability analysis tools are ongoing as part of the program's current verification effort. The purpose of these comparisons is to highlight modeling and analysis differences, verify simulation data sources, identify inconsistencies and minor errors, and ultimately to verify output data as being a good representation of the vehicle and subsystem dynamics. This paper will show selected verification work in both the time and frequency domain from the current design analysis cycle of the SLS for several of the design and analysis simulations. In the time domain, the tools that will be compared are MAVERIC, CLVTOPS, SAVANT, STARS, ARTEMIS, and POST 2. For the frequency domain analysis, the tools to be compared are FRACTAL, SAVANT, and STARS. The paper will include discussion of these tools including their capabilities, configurations, and the uses to which they are put in the SLS program. Determination of the criteria by which the simulations are compared (matching criteria) requires thoughtful consideration, and there are several pitfalls that may occur that can severely punish a simulation if not considered carefully. The paper will discuss these considerations and will present a framework for responding to these issues when they arise. For example, small event timing differences can lead to large differences in mass properties if the criteria are to measure those properties at the same time, or large differences in altitude if the criteria are to measure those properties when the simulation experiences a staging event. Similarly, a tiny difference in phase can lead to large gain margin differences for frequency-domain comparisons of gain margins.

Photocatalytic degradation of surfactants with immobilized TiO2: comparing two reaction systems.

PubMed

Lizama, C; Bravo, C; Caneo, C; Ollino, M

2005-08-01

The photocatalytic degradation of two industrial-grade surfactants, sodium lauryl sulphate (SLS) and sodium dodecylbenzenesulphonate (SDDBS), were achieved using TiO2 immobilised on glass Raschig rings and inside a bent tube of glass, using two different photoreactors in recirculation batch mode with a black light fluorescent tube as irradiation source. The influence of parameters pH, recalculation flow, airflow and number of treatment units were determined. For comparison purposes, the energetic cost of treatment was determined for both reaction systems as the figure-of-merit EE/O, showing that titania supported on glass Raschig rings is a more efficient system than the inner coated spring with TiO2, but this condition is strongly dependent on the surfactant identity. The best conditions for surfactants elimination were used to carry out the treatment of solutions containing two commercial detergents, reaching an 80% of removal in 60 min of irradiation.

Variability of single-leg versus double-leg stance radiographs in the varus knee.

PubMed

Chen, Andrew; Rich, Valerie; Bain, Elizabeth; Sterett, William I

2009-07-01

We evaluated measured radiographic parameter variability between single-leg stance (SLS) and double-leg stance (DLS) radiographs in patients with varus knee malalignment, indicated for high tibial osteotomy. Fifty-three consecutive knees (mean, 49 years; range, 18-79 years) were evaluated for varus thrust. SLS and DLS radiographs were obtained. A single blinded observer measured mechanical axis angles and weight-bearing line (WBL) deviation using a goniometer. Mechanical axis angles averaged 9.1 degrees (DLS) and 11.3 degrees (SLS). SLS radiographs averaged 9% greater WBL medialization than did DLS. Medial opening averaged 16.4 mm (DLS) and 18.8 mm (SLS). DLS and SLS radiographs showed no significant differences in patients without varus thrust. Patients with varus thrust demonstrated differences in mechanical axis angles (DLS, 9.4 degrees; SLS, 12.2 degrees), WBL deviation (12.1% less), medialization (DLS), and medial opening necessary for correction (DLS, 16.6 mm; SLS, 20.3 mm). In varus thrust, SLS radiographs more closely replicate dynamic knee malalignment, possibly providing more accurate measurements of angular deformity.

A novel model of inflammatory pain in human skin involving topical application of sodium lauryl sulfate.

PubMed

Petersen, L J; Lyngholm, A M; Arendt-Nielsen, L

2010-09-01

Sodium lauryl sulfate (SLS) is a known irritant. It releases pro-inflammatory mediators considered pivotal in inflammatory pain. The sensory effects of SLS in the skin remain largely unexplored. In this study, SLS was evaluated for its effect on skin sensory functions. Eight healthy subjects were recruited for this study. Skin sites were randomized to topical SLS 0.25, 0.5, 1, 2% and vehicle for 24 h. Topical capsaicin 1% was applied for 30 min at 24 h after SLS application. Assessments included laser Doppler imaging of local vasodilation and flare reactions, rating of spontaneous pain, assessment of primary thermal and tactile hyperalgesia, and determination of secondary dynamic and static hyperalgesia. SLS induced significant and dose-dependent local inflammation and primary hyperalgesia to tactile and thermal stimulation at 24 h after application, with SLS 2% treatment eliciting results comparable to those observed following treatment with capsaicin 1%. SLS induced no spontaneous pain, small areas of flare, and minimal secondary hyperalgesia. The primary hyperalgesia vanished within 2-3 days, whereas the skin inflammation persisted and was only partly normalized by Day 6. SLS induces profound perturbations of skin sensory functions lasting 2-3 days. SLS-induced inflammation may be a useful model for studying the mechanisms of inflammatory pain.

Novel characteristics of sophorolipids, yeast glycolipid biosurfactants, as biodegradable low-foaming surfactants.

PubMed

Hirata, Yoshihiko; Ryu, Mizuyuki; Oda, Yuka; Igarashi, Keisuke; Nagatsuka, Asami; Furuta, Taro; Sugiura, Masaki

2009-08-01

Sophorolipids (SLs) are a family of glycolipid type biosurfactants, which are largely produced by the non-pathogenic yeast, Candida bombicola. In order to investigate the possibility of SLs for industrial use, here we examined the interfacial activities, cytotoxicity and biodegradability of SLs, and compared these properties with those of two lipopeptide type biosurfactants (surfactin and arthrofactin), sodium laurate (soap, SP) and four kinds of chemically synthesized surfactants including two block-copolymer nonionic surfactants (BPs), polyoxyethylene lauryl ether (AE) and sodium dodecyl sulfate (SDS). It was indicated that SLs had extremely low-foaming properties and high detergency comparable with commercially available low-foaming BPs. These interfacial activities of SLs were maintained under 100 ppm water hardness. Cytotoxicity of SLs on human keratinocytes was the same as surfactin, which has already been commercialized as cosmetic material, but higher than BPs. Moreover, biodegradability of SLs using the OECD Guidelines for Testing of Chemicals (301C, Modified MITI Test) displayed that SLs can be classified as "readily" biodegradable chemicals, which are defined as chemicals that are degraded 60% within 28 days under specified test methods. We observed 61% degradation of SLs on the eighth day of cultivation. Our results indicate that SLs are low-foaming surfactants with high detergency, which also exhibit both low cytotoxicity and readily biodegradable properties.

Molar mass, radius of gyration and second virial coefficient from new static light scattering equations for dilute solutions: application to 21 (macro)molecules.

PubMed

Illien, Bertrand; Ying, Ruifeng

2009-05-11

New static light scattering (SLS) equations for dilute binary solutions are derived. Contrarily to the usual SLS equations [Carr-Zimm (CZ)], the new equations have no need for the experimental absolute Rayleigh ratio of a reference liquid and solely rely on the ratio of scattered intensities of solutions and solvent. The new equations, which are based on polarizability equations, take into account the usual refractive index increment partial differential n/partial differential rho(2) complemented by the solvent specific polarizability and a term proportional to the slope of the solution density rho versus the solute mass concentration rho(2) (density increment). Then all the equations are applied to 21 (macro)molecules with a wide range of molar mass (0.2500 kg mol(-1)), for which the scattered intensity is no longer independent of the scattering angle, the new equations give the same value of the radius of gyration as the CZ equation and consistent values of the second virial coefficient.

Skin irritability to sodium lauryl sulfate is associated with increased positive patch test reactions.

PubMed

Schwitulla, J; Brasch, J; Löffler, H; Schnuch, A; Geier, J; Uter, W

2014-07-01

As previous observations have indicated an inter-relationship between irritant and allergic skin reactions we analysed data of synchronous allergen and sodium lauryl sulfate (SLS) patch tests in terms of a relationship between SLS responsiveness and allergic patch test reactions. To analyse differences in terms of allergen-specific and overall reaction profiles between patients with vs. those without an irritant reaction to SLS. Clinical data of 26 879 patients patch tested from 2008 to 2011 by members of the Information Network of Departments of Dermatology were analysed. After descriptive analyses, including the MOAHLFA index, the positivity ratio and the reaction index, a negative binomial hurdle model was adopted to investigate the correlation between SLS reactivity and positive patch test reactions. Men, patients aged ≥ 40 years and patients with an occupational dermatitis background were over-represented in the SLS-reactive group. Patients with an irritant reaction to SLS showed a higher proportion of weak positive reactions, as well as more questionable and irritant reactions to contact allergens than patients not reactive to SLS. The risk of an additional positive patch test reaction increased by 22% for SLS-reactive patients compared with those who were SLS negative. The marked association between SLS reactivity and the number of positive reactions in patch test patients may be due to nonspecific increased skin reactivity at the moment of patch testing only. However, increased SLS reactivity could also be due to longer-lasting enhanced skin irritability, which may have promoted (poly-)sensitization. Further studies, for example with longitudinal data on patients repeatedly patch tested with SLS and contact allergens, are necessary. © 2014 British Association of Dermatologists.

The effectiveness of dentifrices without and with sodium lauryl sulfate on plaque, gingivitis and gingival abrasion--a randomized clinical trial.

PubMed

Sälzer, S; Rosema, N A M; Martin, E C J; Slot, D E; Timmer, C J; Dörfer, C E; van der Weijden, G A

2016-04-01

The aim of this study was to compare the efficacy of a dentifrice without sodium lauryl sulfate (SLS) to a dentifrice with SLS in young adults aged 18-34 years on gingivitis. One hundred twenty participants (non-dental students) with a moderate gingival inflammation (bleeding on probing at 40-70 % of test sites) were included in this randomized controlled double blind clinical trial. According to randomization, participants had to brush their teeth either with dentifrice without SLS or with SLS for 8 weeks. The primary outcome was bleeding on marginal probing (BOMP). The secondary outcomes were plaque scores and gingival abrasion scores (GA) as well as a visual analogue scale (VAS) score at exit survey. Baseline and end differences were analysed by univariate analysis of covariance (ANCOVA) test, between group differences by independent t test and within groups by paired sample t test. BOMP improved within groups from on average 0.80 at baseline to 0.60 in the group without SLS and to 0.56 in the group with SLS. No statistical difference for BOMP, plaque and gingival abrasion was found between both groups. VAS scores for taste, freshness and foaming effect were significantly in favour of the SLS-containing dentifrice. The test dentifrice without SLS was as effective as a regular SLS dentifrice on gingival bleeding scores and plaque scores. There was no significant difference in the incidence of gingival abrasion. In patients diagnosed with gingivitis, a dentifrice without SLS seems to be equally effective compared to a dentifrice with SLS and did not demonstrate any significant difference in gingival abrasion. In patient with recurrent aphthous ulcers, the absence of SLS may even be beneficial. However, participants indicate that they appreciate the foaming effect of a dentifrice with SLS more.

Improving the hardness of dry granulated tablets containing sodium lauryl sulfate.

PubMed

Moore, Francis; Okelo, Geoffrey; Colón, Ivelisse; Kushner, Joseph

2010-11-15

The impact of the addition of a wetting agent, the surfactant sodium lauryl sulfate (SLS), on the tablet hardness of a dry granulated, solid oral dosage form was investigated. In three batches, SLS was added concurrently with: (1) a poorly soluble, highly hydrophobic active pharmaceutical ingredient (API) and the other excipients prior to the initial blending step, (2) magnesium stearate prior to roller compaction, or (3) magnesium stearate prior to tableting. A fourth batch, which did not contain SLS, served as a control. The maximum hardness of 100 mg, 1/4″-SRC tablets for the four batches--SLS added initially, prior to roller compaction, prior to tableting, and no SLS--were 61±3, 71±3, 89±5, and 86±3N, respectively, suggesting reduced processing of SLS improves tablet hardness by ∼50%. Dissolution of the tablets in 900 ml of simulated gastric fluid with paddles at 75 rpm showed that: (1) there was no impact on the insertion point of SLS into the process on API dissolution, and (2) that the presence of SLS improved dissolution by 5% compared to the control tablets. Adding SLS just prior to tableting can improve tablet hardness and yield similar dissolution performance relative to SLS addition prior to the initial blending step. Copyright © 2010 Elsevier B.V. All rights reserved.

Structural and Functional Dissection of the Heterocyclic Peptide Cytotoxin Streptolysin S*S⃞

PubMed Central

Mitchell, Douglas A.; Lee, Shaun W.; Pence, Morgan A.; Markley, Andrew L.; Limm, Joyce D.; Nizet, Victor; Dixon, Jack E.

2009-01-01

The human pathogen Streptococcus pyogenes secretes a highly cytolytic toxin known as streptolysin S (SLS). SLS is a key virulence determinant and responsible for the β-hemolytic phenotype of these bacteria. Despite over a century of research, the chemical structure of SLS remains unknown. Recent experiments have revealed that SLS is generated from an inactive precursor peptide that undergoes extensive post-translational modification to an active form. In this work, we address outstanding questions regarding the SLS biosynthetic process, elucidating the features of substrate recognition and sites of posttranslational modification to the SLS precursor peptide. Further, we exploit these findings to guide the design of artificial cytolytic toxins that are recognized by the SLS biosynthetic enzymes and others that are intrinsically cytolytic. This new structural information has ramifications for future antimicrobial therapies. PMID:19286651

Charactrisation of particle assemblies by 3D cross correlation light scattering and diffusing wave spectroscopy

NASA Astrophysics Data System (ADS)

Scheffold, Frank

2014-08-01

To characterize the structural and dynamic properties of soft materials and small particles, information on the relevant mesoscopic length scales is required. Such information is often obtained from traditional static and dynamic light scattering (SLS/DLS) experiments in the single scattering regime. In many dense systems, however, these powerful techniques frequently fail due to strong multiple scattering of light. Here I will discuss some experimental innovations that have emerged over the last decade. New methods such as 3D static and dynamic light scattering (3D LS) as well as diffusing wave spectroscopy (DWS) can cover a much extended range of experimental parameters ranging from dilute polymer solutions, colloidal suspensions to extremely opaque viscoelastic emulsions.

Ultra-broadband infrared pump-probe spectroscopy using synchrotron radiation and a tuneable pump.

PubMed

Carroll, Lee; Friedli, Peter; Lerch, Philippe; Schneider, Jörg; Treyer, Daniel; Hunziker, Stephan; Stutz, Stefan; Sigg, Hans

2011-06-01

Synchrotron infrared sources have become popular mainly because of their excellent broadband brilliance, which enables spectroscopically resolved spatial-mapping of stationary objects at the diffraction limit. In this article we focus on an often-neglected further advantage of such sources - their unique time-structure - to bring such broadband spectroscopy to the time domain, for studying dynamic phenomenon down to the 100 ps limit. We describe the ultra-broadband (12.5 to 1.1 μm) Fourier transform pump-probe setup, for condensed matter transmission- and reflection-spectroscopy, installed at the X01DC infrared beam-line of the Swiss Light Source (SLS). The optical pump consists of a widely tuneable 100 ps 1 kHz laser system, covering 94% of the 16 to 1.1 μm range. A thorough description of the system is given, including (i) the vector-modulator providing purely electronic tuning of the pump-probe overlap up to 1 ms with sub-ps time resolution, (ii) the 500 MHz data acquisition system interfaced with the experimental physics and industrial control system (EPICS) based SLS control system for consecutive pulse sampling, and (iii) the step-scan time-slice Fourier transform scheme for simultaneous recording of the dual-channel pumped, un-pumped, and difference spectra. The typical signal/noise ratio of a single interferogram in a 100 ps time slice is 300 (measured during one single 140 s TopUp period). This signal/noise ratio is comparable to that of existing gated Globar pump-probe Fourier transform spectroscopy, but brings up to four orders of magnitude better time resolution. To showcase the utility of broadband pump-probe spectroscopy, we investigate a Ge-on-Si material system similar to that in which optically pumped direct-gap lasing was recently reported. We show that the mid-infrared reflection-spectra can be used to determine the optically injected carrier density, while the mid- and near-infrared transmission-spectra can be used to separate the strong pump-induced absorption and inversion processes present at the direct-gap energy. © 2011 American Institute of Physics

Effect of crystal quality on performance of spin-polarized photocathode

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jin, Xiuguang; Ozdol, Burak; Yamamoto, Masahiro

2014-11-17

GaAs/GaAsP strain-compensated superlattices (SLs) with thickness up to 90-pair were fabricated. Transmission electron microscopy revealed the SLs are of high crystal quality and the introduced strain in SLs layers are fixed in the whole SL layers. With increasing SL pair number, the strain-compensated SLs show a less depolarization than the conventional strained SLs. In spite of the high crystal quality, the strain-compensated SLs also remain slightly depolarized with increasing SL pairs and the decrease in spin-polarization contributes to the spin relaxation time. 24-pair of GaAs/GaAsP strain-compensated SL demonstrates a maximum spin-polarization of 92% with a high quantum efficiency of 1.6%.

Inside The Space Launch System (SLS): Outfitting The World’s Most Powerful Rocket

NASA Image and Video Library

2018-02-13

Find out why NASA’s new deep-space rocket, the Space Launch System (SLS) is more than just big and beautiful. For the world’s most powerful rocket, it takes a lot of “guts.” Engineers have built all the giant structures that will be assembled to form the first SLS rocket, and now they are busy installing and outfitting the rocket’s insides with sensors, cables and other equipment. The rocket’s insides including its incredible flight computers and batteries will ensure SLS can do the job of sending the Orion spacecraft out beyond the Moon farther than any human-rated space vehicle as ever ventured. Learn how the SLS core stage components are being outfitted for the first SLS mission, Exploration Mission-1. Find out more at https://www.nasa.gov/exploration/systems/sls/index.html

Lower-limb kinematics of single-leg squat performance in young adults.

PubMed

Horan, Sean A; Watson, Steven L; Carty, Christopher P; Sartori, Massimo; Weeks, Benjamin K

2014-01-01

To determine the kinematic parameters that characterize good and poor single-leg squat (SLS) performance. A total of 22 healthy young adults free from musculoskeletal impairment were recruited for testing. For each SLS, both two-dimensional video and three-dimensional motion analysis data were collected. Pelvis, hip, and knee angles were calculated using a reliable and validated lower-limb (LL) biomechanical model. Two-dimensional video clips of SLSs were blindly assessed in random order by eight musculoskeletal physiotherapists using a 10-point ordinal scale. To facilitate between-group comparisons, SLS performances were stratified by tertiles corresponding to poor, intermediate, and good SLS performance. Mean ratings of SLS performance assessed by physiotherapists were 8.3 (SD 0.5), 6.8 (SD 0.7), and 4.0 (SD 0.8) for good, intermediate, and poor squats, respectively. Three-dimensional analysis revealed that people whose SLS performance was assessed as poor exhibited increased hip adduction, reduced knee flexion, and increased medio-lateral displacement of the knee joint centre compared to those whose SLS performance was assessed as good (p≤0.05). Overall, poor SLS performance is characterized by inadequate knee flexion and excessive frontal plane motion of the knee and hip. Future investigations of SLS performance should consider standardizing knee flexion angle to illuminate other influential kinematic parameters.

Transcriptome and proteome analyses and the role of atypical calpain protein and autophagy in the spliced leader silencing pathway in Trypanosoma brucei.

PubMed

Hope, Ronen; Egarmina, Katarina; Voloshin, Konstantin; Waldman Ben-Asher, Hiba; Carmi, Shai; Eliaz, Dror; Drori, Yaron; Michaeli, Shulamit

2016-10-01

Under persistent ER stress, Trypanosoma brucei parasites induce the spliced leader silencing (SLS) pathway. In SLS, transcription of the SL RNA gene, the SL donor to all mRNAs, is extinguished, arresting trans-splicing and leading to programmed cell death (PCD). In this study, we investigated the transcriptome following silencing of SEC63, a factor essential for protein translocation across the ER membrane, and whose silencing induces SLS. The proteome of SEC63-silenced cells was analyzed with an emphasis on SLS-specific alterations in protein expression, and modifications that do not directly result from perturbations in trans-splicing. One such protein identified is an atypical calpain SKCRP7.1/7.2. Co-silencing of SKCRP7.1/7.2 and SEC63 eliminated SLS induction due its role in translocating the PK3 kinase. This kinase initiates SLS by migrating to the nucleus and phosphorylating TRF4 leading to shut-off of SL RNA transcription. Thus, SKCRP7.1 is involved in SLS signaling and the accompanying PCD. The role of autophagy in SLS was also investigated; eliminating autophagy through VPS34 or ATG7 silencing demonstrated that autophagy is not essential for SLS induction, but is associated with PCD. Thus, this study identified factors that are used by the parasite to cope with ER stress and to induce SLS and PCD. © 2016 John Wiley & Sons Ltd.

Sodium Lauryl Sulfate Abrogates Human Immunodeficiency Virus Infectivity by Affecting Viral Attachment

PubMed Central

Bestman-Smith, Julie; Piret, Jocelyne; Désormeaux, André; Tremblay, Michel J.; Omar, Rabeea F.; Bergeron, Michel G.

2001-01-01

The microbicidal activity of sodium lauryl sulfate (SLS) against human immunodeficiency virus type 1 (HIV-1) was studied in cultured cells. Pretreatment of HIV-1NL4-3 with SLS decreased, in a concentration-dependent manner, its infectivity when using 1G5 as target cells. In the absence of a viral pretreatment period or when 1G5 cells were pretreated with SLS, the surfactant-induced inactivation of viral infectivity was less pronounced, especially at concentrations between 375 and 550 μM. SLS had no effect on HIV-1 when the virus was adsorbed to 1G5 cells by a 2-h incubation period. SLS almost completely inhibited the fusion process by decreasing the attachment of HIV-1 to target cells. SLS also inhibited the infectivity of HIV-1-based luciferase reporter viruses pseudotyped with the amphotropic murine leukemia virus envelope (which enters cells in a CD4-, CCR5-, and CXCR4-independent manner), indicating that SLS may inactivate other envelope viruses. In contrast, no effect was seen with vesicular stomatitis virus envelope glycoprotein G (which enters cells through receptor-mediated endocytosis) pretreated with up to 700 μM SLS. SLS also decreased, in a dose-dependent manner, the HIV-1-dependent syncytium formation between 1G5 and J1.1 cells after a 24-h incubation. The reduction of luciferase activity was more pronounced when J1.1 cells (which express HIV-1 proteins on their surface) were pretreated with SLS rather than 1G5 cells. Taken together, our results suggest that SLS could represent a candidate of choice for use in vaginal microbicides to prevent the sexual transmission of HIV and possibly other pathogens causing sexually transmitted diseases. PMID:11451679

Natural synergism of acid and lactone type mixed sophorolipids in interfacial activities and cytotoxicities.

PubMed

Hirata, Yoshihiko; Ryu, Mizuyuki; Igarashi, Keisuke; Nagatsuka, Asami; Furuta, Taro; Kanaya, Shigenori; Sugiura, Masaki

2009-01-01

Sophorolipids (SLs) naturally produced from Candida bombicola are a mixture of lactonic (SL-lactone) and acidic (SL-acid) sophorosides of 17-L-hydroxydecanoic acid with an SL-lactone:SL-acid ratio of 72:28. SLs are biodegradable low-foaming surfactants with high detergency and hardness-tolerance properties. To analyze the effect of the SL-lactone:SL-acid ratio on these properties, SL-LXs containing X% SL-lactone, in which X varied from 0 to 100, were prepared and their interfacial activities and cytotoxicities examined. The minimum surface tension values for all SLs examined were comparable. The critical micelle concentration (CMC) was 680 mg/L for SL-L0 and 62-110 mg/L for the other SLs. Interestingly, natural SL (SL-L72) had the lowest surface tension and CMC among all of the SLs examined. The foaming ability and stability of the SLs were dependent on the SL-L content. SL-L0 and L17 had higher foaming values than the other SLs examined in 0-ppm hardness water. These values greatly reduced and became constant when the SL-L content increased over 55%. The detergencies of all of the SLs examined were comparable, except for those of SL-L0 and SL-L100, which were slightly lower than those of the other SLs. These results suggest that natural synergism between SLs creates a better balance for many interfacial activities. The cytotoxicity of SL-L72 was higher than that of SL-L0, but was comparable to that of surfactin, which is commercially available for cosmetic use. The low cytotoxicities and high interfacial properties of SLs increase their usefulness as biocompatible surface active agents for many applications.

Sodium Lauryl Sulfate Stimulates the Generation of Reactive Oxygen Species through Interactions with Cell Membranes.

PubMed

Mizutani, Taeko; Mori, Ryota; Hirayama, Misaki; Sagawa, Yuki; Shimizu, Kenji; Okano, Yuri; Masaki, Hitoshi

2016-12-01

Sodium lauryl sulfate (SLS), a representative anionic surfactant, is well-known to induce rough skin following single or multiple topical applications. The mechanism by which SLS induces rough skin is thought to result from the disruption of skin moisture function consisting of NMF and epidermal lipids. However, a recent study demonstrated that topically applied SLS easily penetrates into the living cell layers of the epidermis, which suggests that physiological alterations of keratinocytes might cause the SLS-induced rough skin. This study was conducted to clarify the effects of SLS on keratinocytes to demonstrate the contribution of SLS to the induction of rough skin. In addition, the potentials of other widely used anionic surfactants to induce rough skin were evaluated. HaCaT keratinocytes treated with SLS had increased levels of intracellular ROS and IL-1α secretion. Application of SLS on the surface of a reconstructed epidermal equivalent also showed the increased generation of ROS. Further, SLS-treated cells showed an increase of intracellular calpain activity associated with the increase of intracellular Ca 2+ concentration. The increase of intracellular ROS was abolished by the addition of BAPTA-AM, a specific chelator of Ca 2+ . In addition, IL-1α also stimulated ROS generation by HaCaT keratinocytes. An ESR spin-labeling study demonstrated that SLS increased the fluidity of membranes of liposomes and cells. Together, those results indicate that SLS initially interacts with cell membranes, which results in the elevation of intracellular Ca 2+ influx. Ca 2+ stimulates the secretion of IL-1α due to the activation of calpain, and also increases ROS generation. IL-1α also stimulates ROS generation by HaCaT keratinocytes. We conclude from these results that the elevation of intracellular ROS levels is one of the causes of SLS-induced rough skin. Finally, among the other anionic surfactants tested, sodium lauryl phosphate has less potential to induce rough skin because of its lower generation of ROS.

Monitoring safety in a phase III real‐world effectiveness trial: use of novel methodology in the Salford Lung Study

PubMed Central

Harvey, Catherine; Brewster, Jill; Bakerly, Nawar Diar; Elkhenini, Hanaa F.; Stanciu, Roxana; Williams, Claire; Brereton, Jacqui; New, John P.; McCrae, John; McCorkindale, Sheila; Leather, David

2016-01-01

Abstract Background The Salford Lung Study (SLS) programme, encompassing two phase III pragmatic randomised controlled trials, was designed to generate evidence on the effectiveness of a once‐daily treatment for asthma and chronic obstructive pulmonary disease in routine primary care using electronic health records. Objective The objective of this study was to describe and discuss the safety monitoring methodology and the challenges associated with ensuring patient safety in the SLS. Refinements to safety monitoring processes and infrastructure are also discussed. The study results are outside the remit of this paper. The results of the COPD study were published recently and a more in‐depth exploration of the safety results will be the subject of future publications. Achievements The SLS used a linked database system to capture relevant data from primary care practices in Salford and South Manchester, two university hospitals and other national databases. Patient data were collated and analysed to create daily summaries that were used to alert a specialist safety team to potential safety events. Clinical research teams at participating general practitioner sites and pharmacies also captured safety events during routine consultations. Confidence in the safety monitoring processes over time allowed the methodology to be refined and streamlined without compromising patient safety or the timely collection of data. The information technology infrastructure also allowed additional details of safety information to be collected. Conclusion Integration of multiple data sources in the SLS may provide more comprehensive safety information than usually collected in standard randomised controlled trials. Application of the principles of safety monitoring methodology from the SLS could facilitate safety monitoring processes for future pragmatic randomised controlled trials and yield important complementary safety and effectiveness data. © 2016 The Authors Pharmacoepidemiology and Drug Safety Published by John Wiley & Sons Ltd. PMID:27804174

Monitoring safety in a phase III real-world effectiveness trial: use of novel methodology in the Salford Lung Study.

PubMed

Collier, Sue; Harvey, Catherine; Brewster, Jill; Bakerly, Nawar Diar; Elkhenini, Hanaa F; Stanciu, Roxana; Williams, Claire; Brereton, Jacqui; New, John P; McCrae, John; McCorkindale, Sheila; Leather, David

2017-03-01

The Salford Lung Study (SLS) programme, encompassing two phase III pragmatic randomised controlled trials, was designed to generate evidence on the effectiveness of a once-daily treatment for asthma and chronic obstructive pulmonary disease in routine primary care using electronic health records. The objective of this study was to describe and discuss the safety monitoring methodology and the challenges associated with ensuring patient safety in the SLS. Refinements to safety monitoring processes and infrastructure are also discussed. The study results are outside the remit of this paper. The results of the COPD study were published recently and a more in-depth exploration of the safety results will be the subject of future publications. The SLS used a linked database system to capture relevant data from primary care practices in Salford and South Manchester, two university hospitals and other national databases. Patient data were collated and analysed to create daily summaries that were used to alert a specialist safety team to potential safety events. Clinical research teams at participating general practitioner sites and pharmacies also captured safety events during routine consultations. Confidence in the safety monitoring processes over time allowed the methodology to be refined and streamlined without compromising patient safety or the timely collection of data. The information technology infrastructure also allowed additional details of safety information to be collected. Integration of multiple data sources in the SLS may provide more comprehensive safety information than usually collected in standard randomised controlled trials. Application of the principles of safety monitoring methodology from the SLS could facilitate safety monitoring processes for future pragmatic randomised controlled trials and yield important complementary safety and effectiveness data. © 2016 The Authors Pharmacoepidemiology and Drug Safety Published by John Wiley & Sons Ltd. © 2016 The Authors Pharmacoepidemiology and Drug Safety Published by John Wiley & Sons Ltd.

The effectiveness of a dentifrice without sodium lauryl sulphate on dental plaque and gingivitis - a randomized controlled clinical trial.

PubMed

Sälzer, S; Rosema, Nam; Hennequin-Hoenderdos, N L; Slot, D E; Timmer, C; Dörfer, C E; Van der Weijden, G A

2017-08-01

The purpose of the study was to evaluate the effect on dental plaque and gingivitis of a dentifrice without sodium lauryl sulphate (SLS) compared to two SLS-containing dentifrices. For this double-blind, parallel study, 90 volunteers having moderate gingival inflammation (≥40%) were randomly divided among three groups: one group using non-SLS dentifrice containing enzymes, colostrum and low concentrations of zinc and two control groups each using different SLS-containing dentifrices. Dental plaque scores (Turesky modification of Quigley & Hein) and gingivitis scores (Bleeding On Marginal Probing) were assessed at baseline, after 2 and 4 weeks. Eighty-nine participants provided evaluable data. A slight decrease in gingivitis scores was observed for all groups over 4 weeks, which was statistically significant for the non-SLS group. Mean values for dental plaque scores did not show major differences over 4 weeks. For both parameters, no significant differences between groups could be observed at any time point. Patient appreciation was in favour of the SLS groups especially regarding the foaming effect. No significant differences could be observed with respect to the effect on plaque and gingivitis between SLS-containing and SLS-free dentifrice containing enzymes, colostrum and low concentration zinc. Patients enjoyed the duration of taste and the 'foaming effect' of SLS-containing dentifrices better. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Comparison of adsorption equilibrium models and error functions for the study of sulfate removal by calcium hydroxyapatite microfibrillated cellulose composite.

PubMed

Hokkanen, Sanna; Bhatnagar, Amit; Koistinen, Ari; Kangas, Teija; Lassi, Ulla; Sillanpää, Mika

2018-04-01

In the present study, the adsorption of sulfates of sodium sulfate (Na 2 SO 4 ) and sodium lauryl sulfate (SLS) by calcium hydroxyapatite-modified microfibrillated cellulose was studied in the aqueous solution. The adsorbent was characterized using elemental analysis, Fourier transform infrared, scanning electron microscope and elemental analysis in order to gain the information on its structure and physico-chemical properties. The adsorption studies were conducted in batch mode. The effects of solution pH, contact time, the initial concentration of sulfate and the effect of competing anions were studied on the performance of synthesized adsorbent for sulfate removal. Adsorption kinetics indicated very fast adsorption rate for sulfate of both sources (Na 2 SO 4 and SLS) and the adsorption process was well described by the pseudo-second-order kinetic model. Experimental maximum adsorption capacities were found to be 34.53 mg g -1 for sulfates of SLS and 7.35 mg g -1 for sulfates of Na 2 SO 4. The equilibrium data were described by the Langmuir, Sips, Freundlich, Toth and Redlich-Peterson isotherm models using five different error functions.

NASA Space Rocket Logistics Challenges

NASA Technical Reports Server (NTRS)

Bramon, Chris; Neeley, James R.; Jones, James V.; Watson, Michael D.; Inman, Sharon K.; Tuttle, Loraine

2014-01-01

The Space Launch System (SLS) is the new NASA heavy lift launch vehicle in development and is scheduled for its first mission in 2017. SLS has many of the same logistics challenges as any other large scale program. However, SLS also faces unique challenges. This presentation will address the SLS challenges, along with the analysis and decisions to mitigate the threats posed by each.

Effect of sodium lauryl sulfate in dissolution media on dissolution of hard gelatin capsule shells.

PubMed

Zhao, Fang; Malayev, Vyacheslav; Rao, Venkatramana; Hussain, Munir

2004-01-01

Sodium lauryl sulfate (SLS) is a commonly used surfactant in dissolution media for poorly water soluble drugs. However, it has occasionally been observed that SLS negatively impacts the dissolution of drug products formulated in gelatin capsules. This study investigated the effect of SLS on the dissolution of hard gelatin capsule shells. The USP paddle method was used with online UV monitoring at 214 nm (peptide bond). Empty size #0 capsule shells were held to the bottom of the dissolution vessel by magnetic three-prong sinkers. SLS significantly slowed down the dissolution of gelatin shells at pH < 5. Visually, the gelatin shells transformed into some less-soluble precipitate under these conditions. This precipitate was found to contain a higher sulfur content than the gelatin control sample by elemental analysis, indicating that SLS is part of the precipitate. Additionally, the slowdown of capsule shell dissolution was shown to be dependent on the SLS concentration and the ionic strength of the media. SLS interacts with gelatin to form a less-soluble precipitate at pH < 5. The use of SLS in dissolution media at acidic pH should be carefully evaluated for gelatin capsule products.

Polymer powders for selective laser sintering (SLS)

NASA Astrophysics Data System (ADS)

Schmid, Manfred; Amado, Antonio; Wegener, Konrad

2015-05-01

Selective Laser Sintering (SLS) is close to be accepted as a production technique (Additive Manufacturing). However, one problem limiting employment of SLS for additive manufacturing in a wide-ranging industrial scope is the narrow variety of applicable polymers. The commonly applied SLS powder to date is polyamide 12 (PA 12). PA 12 or ccompounds of PA 12 (dry blends) are approximately 90 % of complete industrial consumption. The remaining small quantity is distributed on polyamide 11 (PA11) and some other `exotic' polymers (TPU, PEBA, P(E)EK). Industry is awaiting commodity polymers like polypropylene (PP) or polyethylene (PE) crucial to open new market segments. But several approaches launching those polymers failed. But what are the reasons for the difficulties in developing new SLS powders? The contribution is to answer this and highlights the combination of intrinsic and extrinsic polymer properties necessary to generate a polymer powder promising for SLS application. Particle shape, powder distribution, thermal, rheological and optical requirements must be considered and only a particularly controlled property combination leads to successful SLS implementation. Thermal behavior, particle shape and -distribution is discussed in detail, although the other properties can't be disregarded for providing new commercially successful SLS powder finally.

6DOF Testing of the SLS Inertial Navigation Unit

NASA Technical Reports Server (NTRS)

Geohagan, Kevin W.; Bernard, William P.; Oliver, T. Emerson; Strickland, Dennis J.; Leggett, Jared O.

2018-01-01

The Navigation System on the NASA Space Launch System (SLS) Block 1 vehicle performs initial alignment of the Inertial Navigation System (INS) navigation frame through gyrocompass alignment (GCA). In lieu of direct testing of GCA accuracy in support of requirement verification, the SLS Navigation Team proposed and conducted an engineering test to, among other things, validate the GCA performance and overall behavior of the SLS INS model through comparison with test data. This paper will detail dynamic hardware testing of the SLS INS, conducted by the SLS Navigation Team at Marshall Space Flight Center's 6DOF Table Facility, in support of GCA performance characterization and INS model validation. A 6-DOF motion platform was used to produce 6DOF pad twist and sway dynamics while a simulated SLS flight computer communicated with the INS. Tests conducted include an evaluation of GCA algorithm robustness to increasingly dynamic pad environments, an examination of GCA algorithm stability and accuracy over long durations, and a long-duration static test to gather enough data for Allan Variance analysis. Test setup, execution, and data analysis will be discussed, including analysis performed in support of SLS INS model validation.

Use of soil-like substrate for growing plant to enhance closedness of biological lie support system

NASA Astrophysics Data System (ADS)

Gros, J. B.; Lasseur, C.; Tikhomirov, A. A.; Manuskovsky, N. S.; Kovalev, V. S.; Ushakova, S. A.; Zolotukhin, I. G.; Tirranen, L. S.; Gribovskaya, I. V.

Soil-like substrate (SLS) a potential candidate for use for growing plants in closed biological life support systems (BLSS) was studied. SLS was made by successive transformation of wheat straw by oyster mushrooms and Californian worms. Fertility of SLS of different degree of maturity has been tested. Mature SLS contained 9.5 % of humus acids and 4.9 % of fulvic acids. Wheat, bean and cucumber crops cultivated on mature SLS were comparable to crops obtained on a neutral substrate (expanded clay aggregate). In the wheat-SLS system, net CO2 absorption started on the sixth day after sowing and stopped 5 days prior to harvesting whereas in the wheat-neutral substrate system, net CO2 absorption was registered throughout vegetation. In the SLS, dominant bacteria included the spore-forming bacteria of the Bacillus genus and dominant fungi included the genus Trichoderma. In the hydroponic cultivation on neutral substrate dominant bacteria were of the Pseudomonas genus, while most commonly found fungi were species of the Fusarium genus. Consequence of SLS incorporation in artificial BLSS for increasing the closure degree of internal mass exchange in comparison with a neutral substrate is considered.

Interband absorption strength in long-wave infrared type-II superlattices with small and large superlattice periods compared to bulk materials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vurgaftman, I.; Belenky, G., E-mail: gregory.belenky@stonybrook.edu; Lin, Y.

The absorption spectra for the antimonide-based type-II superlattices (SLs) for detection in the long-wave infrared (LWIR) are calculated and compared to the measured data for SLs and bulk materials with the same energy gap (HgCdTe and InAsSb). We include the results for the metamorphic InAsSb{sub x}/InAsSb{sub y} SLs with small periods as well as the more conventional strain-balanced InAs/Ga(In)Sb and InAs/InAsSb SLs on GaSb substrates. The absorption strength in small-period metamorphic SLs is similar to the bulk materials, while the SLs with an average lattice constant matched to GaSb have significantly lower absorption. This is because the electron-hole overlap inmore » the strain-balanced type-II LWIR SLs occurs primarily in the hole well, which constitutes a relatively small fraction of the total thickness.« less

Critical Role for Very-Long Chain Sphingolipids in Invariant Natural Killer T Cell Development and Homeostasis.

PubMed

Saroha, Ashish; Pewzner-Jung, Yael; Ferreira, Natalia S; Sharma, Piyush; Jouan, Youenn; Kelly, Samuel L; Feldmesser, Ester; Merrill, Alfred H; Trottein, François; Paget, Christophe; Lang, Karl S; Futerman, Anthony H

2017-01-01

The role of sphingolipids (SLs) in the immune system has come under increasing scrutiny recently due to the emerging contributions that these important membrane components play in regulating a variety of immunological processes. The acyl chain length of SLs appears particularly critical in determining SL function. Here, we show a role for very-long acyl chain SLs (VLC-SLs) in invariant natural killer T ( i NKT) cell maturation in the thymus and homeostasis in the liver. Ceramide synthase 2-null mice, which lack VLC-SLs, were susceptible to a hepatotropic strain of lymphocytic choriomeningitis virus, which is due to a reduction in the number of i NKT cells. Bone marrow chimera experiments indicated that hematopoietic-derived VLC-SLs are essential for maturation of i NKT cells in the thymus, whereas parenchymal-derived VLC-SLs are crucial for i NKT cell survival and maintenance in the liver. Our findings suggest a critical role for VLC-SL in i NKT cell physiology.

Design and control of rotating soil-like substrate plant-growing facility based on plant water requirement and computational fluid dynamics simulation

NASA Astrophysics Data System (ADS)

Hu, Dawei; Li, Leyuan; Liu, Hui; Zhang, Houkai; Fu, Yuming; Sun, Yi; Li, Liang

It is necessary to process inedible plant biomass into soil-like substrate (SLS) by bio-compost to realize biological resource sustainable utilization. Although similar to natural soil in structure and function, SLS often has uneven water distribution adversely affecting the plant growth due to unsatisfactory porosity, permeability and gravity distribution. In this article, SLS plant-growing facility (SLS-PGF) were therefore rotated properly for cultivating lettuce, and the Brinkman equations coupled with laminar flow equations were taken as governing equations, and boundary conditions were specified by actual operating characteristics of rotating SLS-PGF. Optimal open-control law of the angular and inflow velocity was determined by lettuce water requirement and CFD simulations. The experimental result clearly showed that water content was more uniformly distributed in SLS under the action of centrifugal and Coriolis force, rotating SLS-PGF with the optimal open-control law could meet lettuce water requirement at every growth stage and achieve precise irrigation.

SLS-PLAN-IT: A knowledge-based blackboard scheduling system for Spacelab life sciences missions

NASA Technical Reports Server (NTRS)

Kao, Cheng-Yan; Lee, Seok-Hua

1992-01-01

The primary scheduling tool in use during the Spacelab Life Science (SLS-1) planning phase was the operations research (OR) based, tabular form Experiment Scheduling System (ESS) developed by NASA Marshall. PLAN-IT is an artificial intelligence based interactive graphic timeline editor for ESS developed by JPL. The PLAN-IT software was enhanced for use in the scheduling of Spacelab experiments to support the SLS missions. The enhanced software SLS-PLAN-IT System was used to support the real-time reactive scheduling task during the SLS-1 mission. SLS-PLAN-IT is a frame-based blackboard scheduling shell which, from scheduling input, creates resource-requiring event duration objects and resource-usage duration objects. The blackboard structure is to keep track of the effects of event duration objects on the resource usage objects. Various scheduling heuristics are coded in procedural form and can be invoked any time at the user's request. The system architecture is described along with what has been learned with the SLS-PLAN-IT project.

Biodiesel production from Nannochloropsis gaditana lipids through transesterification catalyzed by Rhizopus oryzae lipase.

PubMed

Navarro López, Elvira; Robles Medina, Alfonso; González Moreno, Pedro Antonio; Esteban Cerdán, Luis; Martín Valverde, Lorena; Molina Grima, Emilio

2016-03-01

Biodiesel (fatty acid methyl esters, FAMEs) was produced from saponifiable lipids (SLs) extracted from wet Nannochloropsis gaditana biomass using methanolysis catalyzed by Rhizopus oryzae intracellular lipase. SLs were firstly extracted with ethanol to obtain 31 wt% pure SLs. But this low SL purity also gave a low biodiesel conversion (58%). This conversion increased up to 80% using SLs purified by crystallization in acetone (95 wt% purity). Polar lipids play an important role in decreasing the reaction velocity - using SLs extracted with hexane, which have lower polar lipid content (37.4% versus 49.0% using ethanol), we obtained higher reaction velocities and less FAME conversion decrease when the same lipase batch was reused. 83% of SLs were transformed to biodiesel using a 70 wt% lipase/SL ratio, 11:1 methanol/SL molar ratio, 10 mL t-butanol/g SLs after 72 h. The FAME conversion decreased to 71% after catalyzing three reactions with the same lipase batch. Copyright © 2015 Elsevier Ltd. All rights reserved.

NASA Space Launch System: An Enabling Capability for Discovery

NASA Technical Reports Server (NTRS)

Creech, Stephen D.

2014-01-01

SLS provides capability for human exploration missions. 70 t configuration enables EM-1 and EM-2 flight tests. Evolved configurations enable missions including humans to Mars. u? SLS offers unrivaled benefits for a variety of missions. 70 t provides greater mass lift than any contemporary launch vehicle; 130 t offers greater lift than any launch vehicle ever. With 8.4m and 10m fairings, SLS will over greater volume lift capability than any other vehicle. center dot Initial ICPS configuration and future evolution will offer high C3 for beyond- Earth missions. SLS is currently on schedule for first launch in December 2017. Preliminary design completed in July 2013; SLS is now in implementation. Manufacture and testing are currently underway. Hardware now exists representing all SLS elements.

Structural and Optical Studies of ZnCdSe/ZnSe/ZnMgSSe Separate Confinement Heterostructures with Different Buffer Layers

NASA Astrophysics Data System (ADS)

Tu, Ru-Chin; Su, Yan-Kuin; Huang, Ying-Sheng; Chen, Giin-Sang; Chou, Shu-Tsun

1998-09-01

Detailed structural and optical studies of ZnCdSe/ZnSe/ZnMgSSe separate confinementheterostructures (SCH) grown on ZnSe, ZnSe/ZnSSe strained-layer superlattices (SLS),and GaAs buffer layers at the II VI/GaAs interface have been carried out by employingtransmission electron microscopy, variable temperature photoluminescence (PL), andcontactless electroreflectance (CER) measurements. A significant improvement onthe defect reduction and the optical quality has been observed by using either theZnSe/ZnSSe SLS or GaAs as the buffer layers when compared to that of the sample usingonly ZnSe as the buffer layer. However, the sample grown with the SLS buffer layersreveals a room temperature PL intensity higher than that of the sample grown witha GaAs buffer layer, which may still suffer from the great ionic differences betweenthe II V and III V atoms. Using 15 K CER spectra, we have also studied variousexcitonic transitions originating from strained Zn0.80Cd0.20Se/ZnSe single quantumwell in SCH with different buffer layers. An analysis of the CER spectra has ledto the identification of various excitonic transitions, mnH (L), between the mthconduction band state and the nth heavy (light)-hole band state. An excellentagreement between experiments and theoretical calculations based on the envelopefunction approximation model has been achieved.

Softening of the stiffness of bottle-brush polymers by mutual interaction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bolisetty, S.; Airaud, C.; Rosenfeldt, S.

2007-04-15

We study bottle-brush macromolecules in a good solvent by small-angle neutron scattering (SANS), static light scattering (SLS), and dynamic light scattering (DLS). These polymers consist of a linear backbone to which long side chains are chemically grafted. The backbone contains about 1600 monomer units (weight average) and every second monomer unit carries side chains with approximately 60 monomer units. The SLS and SANS data extrapolated to infinite dilution lead to the form factor of the polymer that can be described in terms of a wormlike chain with a contour length of 380 nm and a persistence length of 17.5 nm.more » An analysis of the DLS data confirms these model parameters. The scattering intensities taken at finite concentration can be modeled using the polymer reference interaction site model. It reveals a softening of the bottle-brush polymers caused by their mutual interaction. We demonstrate that the persistence decreases from 17.5 nm down to 5 nm upon increasing the concentration from dilute solution to the highest concentration (40.59 g/l) under consideration. The observed softening of the chains is comparable to the theoretically predicted decrease of the electrostatic persistence length of linear polyelectrolyte chains at finite concentrations.« less

NASA Space Flight Vehicle Fault Isolation Challenges

NASA Technical Reports Server (NTRS)

Neeley, James R.; Jones, James V.; Bramon, Christopher J.; Inman, Sharon K.; Tuttle, Loraine

2016-01-01

The Space Launch System (SLS) is the new NASA heavy lift launch vehicle in development and is scheduled for its first mission in 2018.SLS has many of the same logistics challenges as any other large scale program. However, SLS also faces unique challenges related to testability. This presentation will address the SLS challenges for diagnostics and fault isolation, along with the analyses and decisions to mitigate risk..

Gamma ray shielding characteristic of BiZnBo-SLS and PbZnBo-SLS glass

NASA Astrophysics Data System (ADS)

Syuhada Ahmad, Nor; Shahrim Mustafa, Iskandar; Mansor, Ishak; Malik, Muhammad Fadhirul Izwan bin Abdul; Ain Nabilah Razali, Nur; Nordin, Sufiniza

2018-05-01

The radiation shielding and optical properties of x [RmOn] (0.5‑x) [ZnO] 0.2 [B2O3] 0.3 [SLS], where RmOn are Bi2O3 and PbO with x = 0.05, 0.10, 0.20, 0.30, 0.40, and 0.45 have been prepared by using the melt-quenching method at 1200 °C and was investigated on their physical, structural and gamma ray shielding properties. Field-emission scanning electron microscope (FESEM) data revealed that the particle morphologies is aggregated and irregular in shapes and size. Energy dispersive x-ray spectroscopy (EDS) elemental mapping data confirmed that all mentioned element all present on the prepared glass. Soda Lime Silica (SLS) that is mainly composed of SiO2 has been utilized in this study as the source of SiO2 for fabrication of glass system. From the result, the density and molar volume of both glass samples increased as Bi2O3 and PbO content increased. The gamma ray shielding properties, such as linear attenuation and mass attenuation coefficient, were increased while half value layer (HVL) and mean free path (MFP) were decreased as the increased in Bi2O3 and PbO concentrations. It is recognized that the mass attenuation coefficient value of Bi2O3 and PbO glass are slightly different. From this study, it can be concluded that from the non-toxicity and shielding point of view, the bismuth glass is a good shield to gamma radiation as compared to lead glass.

Effects of sodium lauryl sulphate (SLS), present in dentifrice, on volatile sulphur compound (VSC) formation in morning bad breath.

PubMed

Peruzzo, Daiane Cristina; Salvador, Sérgio Luis; Sallum, Antonio Wilson; da Nogueira-Filho, Getúlio Rocha

2008-10-01

The purpose of the present investigation was to evaluate the effects of sodium lauryl sulphate (SLS), present in a commercial dentifrice, on the formation of volatile sulphur compounds (VSC) and tongue coating in a panel of periodontally healthy subjects. A two-step blinded, crossover, randomized study was carried out in 25 dental students with healthy periodontium; these were divided into two experimental groups: SLS (dentifrice with SLS) and WSLS (dentifrice without SLS). The volunteers received the designated dentifrice and a new toothbrush for a 3x/day brushing regimen for 2 periods of 30 days. A seven-day washout interval was used between the periods. The assessed parameters were: plaque index (PI), gingival index (GI), organoleptic breath (ORG), VSC levels by portable sulphide monitor before (H1) and after (H2) cleaning of the tongue, tongue coating wet weight (TC) and benzoyl-DL-arginine-naphthylamide (BANA) test from tongue coating samples. The intra-group analysis showed a decrease in the median of organoleptic scores from 3 to 2 after 30 days for the SLS group (p < 0.05). The inter-group analysis showed lower values in ORG and H1 for the SLS group (p < 0.05). There was no difference between the amount of TC in SLS and WSLS groups. In the BANA test, the presence of SLS did not affect the BANA number of +/- results (p > 0.05). These findings suggest that sodium lauryl sulphate (SLS), present in dentifrice, appears to prevent VSC formation in morning bad breath regardless of the amount of tongue coating in periodontally healthy subjects.

Comparison of hamstring and quadriceps femoris electromyographic activity between men and women during a single-limb squat on both a stable and labile surface.

PubMed

Youdas, James W; Hollman, John H; Hitchcock, James R; Hoyme, Gregory J; Johnsen, Jeremiah J

2007-02-01

The purpose of this study was to determine if women are quadriceps dominant and men are hamstring dominant during the performance of a partial single-leg squat (SLS) on both a stable and labile ground surface against body weight resistance. Thirty healthy participants (15 men and 15 women) performed an SLS on both a stable surface and a 6.4-cm-thick vinyl pad. Surface electromyographic (EMG) recordings were obtained from the quadriceps femoris and hamstring muscles during the extension phase of the SLS. Statistical analysis revealed that women produced 14% more EMG activity (p = 0.04) in their quadriceps than the men during the SLS on a stable surface, whereas the men generated 18% more EMG activity (p = 0.04) in their hamstrings than the women during the SLS on a labile surface. Additionally, we found a statistically significant sex effect (p = 0.048) for the hamstring/quadriceps (H/Q) EMG ratio, which was 2.25 and 0.62, respectively, for men and women on the stable surface and 2.52 and 0.71, respectively, on the labile surface. We concluded that women are quadriceps dominant and men are hamstring dominant during the performance of SLS against body weight resistance on either a stable or labile surface condition. During an SLS, men showed an H/Q ratio approximately 3.5 times larger than their female counterparts, suggesting that men activate their hamstrings more effectively than women during an SLS. According to our data, the SLS may not be an ideal exercise for activating the hamstring muscles in women without additional neuromuscular training techniques, because women are quadriceps dominant during the SLS.

Effect of the Wetting Agent Sodium Lauryl Sulfate on the Pharmacokinetics of Alectinib: Results From a Bioequivalence Study in Healthy Subjects.

PubMed

Morcos, Peter N; Parrott, Neil; Banken, Ludger; Timpe, Carsten; Lindenberg, Marc; Guerini, Elena; Dall, Georgina; Bogman, Katrijn; Sturm, Carolina; Zeaiter, Ali; Martin-Facklam, Meret; Phipps, Alex

2017-05-01

The anaplastic lymphoma kinase (ALK) inhibitor alectinib is an effective treatment for ALK-positive non-small-cell lung cancer. This bioequivalence study evaluated the in vivo performance of test 3 formulations with the reduced wetting agent sodium lauryl sulfate (SLS) content. This randomized, 4-period, 4-sequence, crossover study compared alectinib (600 mg) as 25%, 12.5%, and 3% SLS hard capsule formulations with the reference 50% SLS clinical formulation in healthy subjects under fasted conditions (n = 49), and following a high-fat meal (n = 48). Geometric mean ratios and 90% confidence intervals (CIs) for C max , AUC 0-last , and AUC 0-∞ of alectinib, its major active metabolite, M4, and alectinib plus M4 were determined for the test formulations versus the reference formulation. Bioequivalence was concluded if the 90%CIs were within the 80% to 125% boundaries. The 25% SLS formulation demonstrated bioequivalence to the reference 50% SLS formulation for C max , AUC 0-last , and AUC 0-∞ of alectinib, M4, and alectinib plus M4 under both fasted and fed conditions. Further reductions in SLS content (12.5% and 3% SLS) did not meet the bioequivalence criteria. Cross-group comparisons showed an approximately 3-fold positive food effect. Reducing SLS to 25% resulted in a formulation that is bioequivalent to the current 50% SLS formulation used in alectinib pivotal trials. © 2016, The American College of Clinical Pharmacology.

Suitability of II-VI semiconductors for photonic applications: common-anion versus common-cation superlattices

NASA Astrophysics Data System (ADS)

Tit, Nacir

2003-12-01

Based on the sp3s tight-binding method, the electronic band strcutures of both common-anion and common-cation II-VI superlattices (SLs) are investigated. As models, we took for the former the case of CdTe/ZnTe(001) SLs where the common anion is confirmed to yield a vanishing or a small valence-band offset (VBO) and the biaxial strain, of course, contributes in the valence-band splittings and yield type-I SLs in most of the studied cases. Whereas, we tok as a second model two different SLs: the ZnS/ZnSe(001) and ZnSe/ZnTe(001) SLs. We have confirmed that the common-cation SLs cannot have a vanishing conduction-band offsets (CBO), as speculated, but rather the CBO could be as large as the VBO. The biaxial strain, again, can participate here in the formation of the band offsets and yield either type-I SLs, as in the case of the ZnS/ZnSe, or type-II SLs, as in the case of ZnSe/ZnTe. Moreover, the reason why some type-II SLs, such as ZnSe/ZnTe(001), could be useful as photonic devices is explained by the tendency of the carriers to confine near the interface as a result of a strong photoluminenscence data and conclusions have been drawn about the strain morpholgy and the structural and optical qualities of the experimental samples.

Cytotoxic 1-deoxysphingolipids are metabolized by a cytochrome P450-dependent pathway[S

PubMed Central

Alecu, Irina; Othman, Alaa; Penno, Anke; Saied, Essa M.; Arenz, Christoph; von Eckardstein, Arnold; Hornemann, Thorsten

2017-01-01

The 1-deoxysphingolipids (1-deoxySLs) are atypical sphingolipids (SLs) that are formed when serine palmitoyltransferase condenses palmitoyl-CoA with alanine instead of serine during SL synthesis. The 1-deoxySLs are toxic to neurons and pancreatic β-cells. Pathologically elevated 1-deoxySLs cause the inherited neuropathy, hereditary sensory autonomic neuropathy type 1 (HSAN1), and are also found in T2D. Diabetic sensory polyneuropathy (DSN) and HSAN1 are clinically very similar, suggesting that 1-deoxySLs may be implicated in both pathologies. The 1-deoxySLs are considered to be dead-end metabolites, as they lack the C1-hydroxyl group, which is essential for the canonical degradation of SLs. Here, we report a previously unknown metabolic pathway, which is capable of degrading 1-deoxySLs. Using a variety of metabolic labeling approaches and high-resolution high-accuracy MS, we identified eight 1-deoxySL downstream metabolites, which appear to be formed by cytochrome P450 (CYP)4F enzymes. Comprehensive inhibition and induction of CYP4F enzymes blocked and stimulated, respectively, the formation of the downstream metabolites. Consequently, CYP4F enzymes might be novel therapeutic targets for the treatment of HSAN1 and DSN, as well as for the prevention of T2D. PMID:27872144

NASA Space Rocket Logistics Challenges

NASA Technical Reports Server (NTRS)

Neeley, James R.; Jones, James V.; Watson, Michael D.; Bramon, Christopher J.; Inman, Sharon K.; Tuttle, Loraine

2014-01-01

The Space Launch System (SLS) is the new NASA heavy lift launch vehicle and is scheduled for its first mission in 2017. The goal of the first mission, which will be uncrewed, is to demonstrate the integrated system performance of the SLS rocket and spacecraft before a crewed flight in 2021. SLS has many of the same logistics challenges as any other large scale program. Common logistics concerns for SLS include integration of discreet programs geographically separated, multiple prime contractors with distinct and different goals, schedule pressures and funding constraints. However, SLS also faces unique challenges. The new program is a confluence of new hardware and heritage, with heritage hardware constituting seventy-five percent of the program. This unique approach to design makes logistics concerns such as commonality especially problematic. Additionally, a very low manifest rate of one flight every four years makes logistics comparatively expensive. That, along with the SLS architecture being developed using a block upgrade evolutionary approach, exacerbates long-range planning for supportability considerations. These common and unique logistics challenges must be clearly identified and tackled to allow SLS to have a successful program. This paper will address the common and unique challenges facing the SLS programs, along with the analysis and decisions the NASA Logistics engineers are making to mitigate the threats posed by each.

Single leg separation prevalence among explanted Björk-Shiley prosthetic heart valves.

PubMed

Blot, William J; Signorello, Lisa B; Cohen, Sarah S; Ibrahim, Michel A

2007-11-01

Björk-Shiley convexo-concave (BSCC) prosthetic heart valves are believed to have been implanted in over 86,000 patients worldwide. Limited data are available on the prevalence of single leg separations (SLS) of the valves' outlet struts, a potential precursor to complete valve fracture. Data maintained by the manufacturer, including results of examinations for SLS in explanted valves, were merged with available information on the characteristics of the valve. The prevalence of SLS in the examined valves was calculated according to valve angle, size, position, and study. Among 343 examined valves, the overall prevalence of SLS was 8.2%, but this varied significantly by valve size, being three-fold higher among 29+ mm valves than among smaller valves, with statistically non-significantly higher prevalences among mitral than aortic, and among 70 degrees than 60 degrees valves. By applying the size, position and angle-specific SLS prevalences to the worldwide valve distribution, it is estimated that SLS may be present in 6.8% (95% confidence limits 4.1-9.4%) of all BSCC valves. These findings suggest that SLS may affect between 820 and 1,880 of the almost 20,000 BSCC valves among surviving patients worldwide. Such estimates help frame the context for potential patient screenings, should imaging and acoustic techniques to detect SLS become available.

The role of strigolactones during plant interactions with the pathogenic fungus Fusarium oxysporum.

PubMed

Foo, Eloise; Blake, Sara N; Fisher, Brendan J; Smith, Jason A; Reid, James B

2016-06-01

Strigolactones (SLs) do not influence spore germination or hyphal growth of Fusarium oxysporum. Mutant studies revealed no role for SLs but a role for ethylene signalling in defence against this pathogen in pea. Strigolactones (SLs) play important roles both inside the plant as a hormone and outside the plant as a rhizosphere signal in interactions with mycorrhizal fungi and parasitic weeds. What is less well understood is any potential role SLs may play in interactions with disease causing microbes such as pathogenic fungi. In this paper we investigate the influence of SLs on the hemibiotrophic pathogen Fusarium oxysporum f.sp. pisi both directly via their effects on fungal growth and inside the plant through the use of a mutant deficient in SL. Given that various stereoisomers of synthetic and naturally occuring SLs can display different biological activities, we used (+)-GR24, (-)-GR24 and the naturally occurring SL, (+)-strigol, as well as a racemic mixture of 5-deoxystrigol. As a positive control, we examined the influence of a plant mutant with altered ethylene signalling, ein2, on disease development. We found no evidence that SLs influence spore germination or hyphal growth of Fusarium oxysporum and that, while ethylene signalling influences pea susceptibility to this pathogen, SLs do not.

Selective laser sintering in biomedical engineering.

PubMed

Mazzoli, Alida

2013-03-01

Selective laser sintering (SLS) is a solid freeform fabrication technique, developed by Carl Deckard for his master's thesis at the University of Texas, patented in 1989. SLS manufacturing is a technique that produces physical models through a selective solidification of a variety of fine powders. SLS technology is getting a great amount of attention in the clinical field. In this paper the characteristics features of SLS and the materials that have been developed for are reviewed together with a discussion on the principles of the above-mentioned manufacturing technique. The applications of SLS in tissue engineering, and at-large in the biomedical field, are reviewed and discussed.

1300479

NASA Image and Video Library

2013-06-18

TODD MAY, LEFT, MANAGER OF THE SLS PROGRAM AT THE MARSHALL CENTER, DISCUSSES THE ROCKET'S SPECIFICATIONS WITH LEROY CAIN, WHO HEADS THE INDEPENDENT STANDING REVIEW BOARD FOR SLS, DURING THE SLS PROGRAM'S PRELIMINARY DESIGN REVIEW. THE REVIEW KICKED OFF JUNE 18-19

A critical evaluation of fasted state simulating gastric fluid (FaSSGF) that contains sodium lauryl sulfate and proposal of a modified recipe.

PubMed

Aburub, Aktham; Risley, Donald S; Mishra, Dinesh

2008-01-22

The aim of this work is to evaluate one of the most commonly used fasted state simulating gastric fluids (FaSSGFs), which contains sodium lauryl sulfate (SLS) (FaSSGF(SLS)), and propose a more appropriate surfactant concentration. Surface tension studies clearly show that the critical micelle concentration (CMC) of SLS in the relevant media (a media whose pH and sodium chloride concentration are representative of physiological conditions) is significantly lower (p<0.05) than 8.67 mM, which is the SLS concentration in FaSSGF(SLS). The CMC of SLS in the relevant media was determined to be 1.75 mM. Based on this a modified recipe is proposed in which the concentration of SLS is sufficient to achieve a surface tension similar to that in vivo without causing artificial micellar solubilization. Solubility, intrinsic dissolution, and GastroPlus modeling studies are presented to support and give rationale for the modified recipe. In addition, a comparison between the modified recipe and other FaSSGFs reported in the literature is made.

Space Launch System for Exploration and Science

NASA Astrophysics Data System (ADS)

Klaus, K.

2013-12-01

Introduction: The Space Launch System (SLS) is the most powerful rocket ever built and provides a critical heavy-lift launch capability enabling diverse deep space missions. The exploration class vehicle launches larger payloads farther in our solar system and faster than ever before. The vehicle's 5 m to 10 m fairing allows utilization of existing systems which reduces development risks, size limitations and cost. SLS lift capacity and superior performance shortens mission travel time. Enhanced capabilities enable a myriad of missions including human exploration, planetary science, astrophysics, heliophysics, planetary defense and commercial space exploration endeavors. Human Exploration: SLS is the first heavy-lift launch vehicle capable of transporting crews beyond low Earth orbit in over four decades. Its design maximizes use of common elements and heritage hardware to provide a low-risk, affordable system that meets Orion mission requirements. SLS provides a safe and sustainable deep space pathway to Mars in support of NASA's human spaceflight mission objectives. The SLS enables the launch of large gateway elements beyond the moon. Leveraging a low-energy transfer that reduces required propellant mass, components are then brought back to a desired cislunar destination. SLS provides a significant mass margin that can be used for additional consumables or a secondary payloads. SLS lowers risks for the Asteroid Retrieval Mission by reducing mission time and improving mass margin. SLS lift capacity allows for additional propellant enabling a shorter return or the delivery of a secondary payload, such as gateway component to cislunar space. SLS enables human return to the moon. The intermediate SLS capability allows both crew and cargo to fly to translunar orbit at the same time which will simplify mission design and reduce launch costs. Science Missions: A single SLS launch to Mars will enable sample collection at multiple, geographically dispersed locations and a low-risk, direct return of Martian material. For the Europa Clipper mission the SLS eliminates Venus and Earth flybys, providing a direct launch to the Jovian system, arriving four years earlier than missions utilizing existing launch vehicles. This architecture allows increased mass for radiation shielding, expansion of the science payload and provides a model for other outer planet missions. SLS provides a direct launch to the Uranus system, reducing travel time by two years when compared to existing launch capabilities. SLS can launch the Advanced Technology Large-Aperture Space Telescope (ATLAST 16 m) to SEL2, providing researchers 10 times the resolution of the James Webb Space Telescope and up to 300 times the sensitivity of the Hubble Space Telescope. SLS is the only vehicle capable of deploying telescopes of this mass and size in a single launch. It simplifies mission design and reduces risks by eliminating the need for multiple launches and in-space assembly. SLS greatly shortens interstellar travel time, delivering the Interstellar Explorer to 200 AU in about 15 years with a maximum speed of 63 km/sec--13.3 AU per year (Neptune orbits the sun at an approximate distance of 30 AU ).

Forward Skirt Structural Testing on the Space Launch System (SLS) Program

NASA Technical Reports Server (NTRS)

Lohrer, J. D.; Wright, R. D.

2016-01-01

Structural testing was performed to evaluate heritage forward skirts from the Space Shuttle program for use on the NASA Space Launch System (SLS) program. Testing was needed because SLS ascent loads are 35% higher than Space Shuttle loads. Objectives of testing were to determine margins of safety, demonstrate reliability, and validate analytical models. Testing combined with analysis was able to show heritage forward skirts were acceptable to use on the SLS program.

Investigation on the interaction of catalase with sodium lauryl sulfonate and the underlying mechanisms.

PubMed

Wang, Jing; Jia, Rui; Wang, Jiaxi; Sun, Zhiqiang; Wu, Zitao; Liu, Rutao; Zong, Wansong

2018-02-01

As a classic type of anionic surfactants, sodium lauryl sulfonate (SLS) might change the structure and function of antioxidant enzyme catalase (CAT) through their direct interactions. However, the underlying molecular mechanism is still unknown. This study investigated the direct interaction of SLS with CAT molecule and the underlying mechanisms using multi-spectroscopic methods, isothermal titration calorimetry, and molecular docking studies. No obvious effects were observed on CAT structure and activity under low SLS concentration exposure. The particle size of CAT molecule decreased and CAT activity was slightly inhibited under high SLS concentration exposure. SLS prefers to bind to the interface of CAT mainly via van der Waals' forces and hydrogen bonds. Subsequently, SLS interacts with the amino acid residues around the heme groups of CAT via hydrophobic interactions and might inhibit CAT activity. © 2017 Wiley Periodicals, Inc.

Inflammatory reaction of the anterior dorsal tongue presumably to sodium lauryl sulfate within toothpastes: a triple case report.

PubMed

Brown, Ronald S; Smith, Langston; Glascoe, Alison L

2018-02-01

Sodium lauryl sulfate (SLS), a popular surface active agent ingredient within toothpastes, is known for its foaming action. Surface active agents increase the effectiveness of toothpastes with respect to dental plaque removal. SLS is a known irritant and also has allergenic potential. The authors report 3 patients with oral pain secondary to inflammation of the dorsal anterior tongue. These patients were all using toothpastes with SLS as an ingredient. The dorsal tongue lesions and oral pain resolved upon switching to toothpastes without SLS as an ingredient. Clinicians should be aware of the potential of SLS within toothpastes to cause oral mucosal inflammatory reactions of the anterior dorsal tongue. To our knowledge, these are the first case reports of oral mucosal inflammatory reactions of the anterior dorsal tongue associated with SLS containing toothpastes. Copyright © 2017 Elsevier Inc. All rights reserved.

NASA's Space Launch System (SLS) Program: Mars Program Utilization

NASA Technical Reports Server (NTRS)

May, Todd A.; Creech, Stephen D.

2012-01-01

NASA's Space Launch System is being designed for safe, affordable, and sustainable human and scientific exploration missions beyond Earth's orbit (BEO), as directed by the NASA Authorization Act of 2010 and NASA's 2011 Strategic Plan. This paper describes how the SLS can dramatically change the Mars program's science and human exploration capabilities and objectives. Specifically, through its high-velocity change (delta V) and payload capabilities, SLS enables Mars science missions of unprecedented size and scope. By providing direct trajectories to Mars, SLS eliminates the need for complicated gravity-assist missions around other bodies in the solar system, reducing mission time, complexity, and cost. SLS's large payload capacity also allows for larger, more capable spacecraft or landers with more instruments, which can eliminate the need for complex packaging or "folding" mechanisms. By offering this capability, SLS can enable more science to be done more quickly than would be possible through other delivery mechanisms using longer mission times.

Heterogeneous chemical reactions: Preparation of monodisperse latexes

NASA Technical Reports Server (NTRS)

Vanderhoff, J. W.; Micale, F. J.; El-Aasser, M. S.; Sterk, A. A.; Bethke, G. W.

1977-01-01

It is demonstrated that a photoinitiated emulsion polymerization can be carried out to a significant conversion in a SPAR rocket prototype polymerization vessel within the six minutes allowed for the experiment. The percentage of conversion was determined by both dilatometry and gravimetric methods with good agreement. The experimental results lead to the following conclusions: (1) emulsion polymerizations can be carried out to conversions as high as 75%, using a stable micellized styrene-SLS system plus photoinitiator; (2) dilatometry can be used to accurately determine both the rate and conversion of polymerization; (3) thermal expansion due to the light source and heat of reaction is small and can be corrected for if necessary; (4) although seeded emulsion polymerizations are unfavorable in photoinitiation, as opposed to chemical initiation, polymerizations can be carried out to at least 15% conversion using 7940A seed particles, with 0.05% solids; and (5) photoinitiation should be used to initiate polymerization in the SPAR rocket experiments because of the mechanical simplicity of the experiment.

Production characteristics of the complex "SLS-vegetables" as the element of bioregenerative life support system

NASA Astrophysics Data System (ADS)

Velichko, Vladimir; Tikhomirov, Alexander A.; Ushakova, Sofya; Tirranen, Lyalya; Gros, Jean-Bernard; Lasseur, Christophe

Previously we had shown possibility of long-term cultivation of wheat and radish uneven-aged conveyer on the soil-like substrate (SLS) with periodic introduction in the SLS of edible (in the form of a mineral solution after physicochemical burning) and inedible biomass of the plants grown on it. The given work was aimed at the study of production characteristics of the plants cultivated on the SLS with a periodic introduction of plant biomass, which consisted of harvested inedible biomass and wheat straw. The wheat straw was introduced in the SLS to compensate carrying out of mineral elements from the SLS with the edible biomass of the harvested plants. Also possibility of joint cultivation of the chosen vegetable plants under the given way of plant inedible biomass introduction in the SLS was estimated. Chufa (Cyperus esculentus L.), radish (Raphanus sativus L.) and lettuce (Lactuca sativa L.) were taken as the objects of research. Plants were grown in the regime of the three-species uneven-aged conveyer. Before each next planting of plants we introduced in the SLS all inedible biomass of earlier harvested plants and wheat straw. The amount of introduced wheat straw depended on nitrogen content in edible biomass of the harvested plants. Plants irrigation was performed by means of common nutrient solution containing mineral elements extracted from the SLS. 2 concentration in a vegetation chamber was maintained in limits from 0.1The work was carried out under support of SB RAS grant 132 and INTAS grant 05-1000008-8010

The Statitical and Case studies of the Thermospheric Enhanced Sodium Layers (TeSLs)

NASA Astrophysics Data System (ADS)

Xue, X.; Li, G.; She, C. Y.; Dou, X.

2015-12-01

We report the thermospheric enhanced sodium layers (TeSLs) observed at low and middle latitude region. Based on the statistical results of the TeSLs observed at Hainan, China (20.0N), a low latitude region, during the year 2011 - 2012, we found a good correlation between the TeSLs and the ionospheric counterparts in E region. For nine of the total 10 TeSLs, which were observed by a sodium lidar, the adjacent ionospheric observations from the COSMIC radio occultation and ionosondes exhibited abrupt perturbations in the RO SNR profiles and spread Es in the ionograms, respectively, indicating the existence of large-scale complex Es. Further, all the TeSLs, which had the co-observations by a VHF radar located nearby, were accompanied by the E region field-aligned irregularity (FAI) echoes. And seven FAIs (7/10) showed evident upwelling structure covering altitudes of 100 -- 140 km, well correlated with the development of the TeSLs. The occurrence of the large-scale complex Es possibly implies the direct altitude modulation of the horizontal Es layers by the atmospheric waves or the strong eastward polarization electric fields, which contribute the formation the FAI structures. In the course of the altitude modulation of the Es layers, sufficient ions (including sodium ions) and electrons could be accumulated in the upper altitude during the upward motion of the FAI plasma and benefits the formation of TeSLs through the chemical reaction. Two TeSL cases observed at Fort Collins, CO (20.0N), a middle latitude region, during day of year (DOY) 177 - 179 and DOY 191 during the year 2003. The enhanced sodium density in the lower thermospheric region provided the simultaneous observations for the horizontal wind and temperature. The TeSLs observed at Fort Collins had the similar feathers, i.e., they appeared at approximately 110 km and propagated with a downward speed of 1.5 - 2.5 km/hr, meanwhile, the higher temperature with approximately 50K increase and strong horizontal wind shear were accompanied with the TeSLs. Further investigation indicated that the TeSLs might be caused mainly by the ions vertical convergence due to horizontal wind-shear induced by the semi-diurnal tides, and the temperature enhancement at the altitude of 110 km had little contributions to the formation of TeSLs.

In situ process monitoring in selective laser sintering using optical coherence tomography

NASA Astrophysics Data System (ADS)

Gardner, Michael R.; Lewis, Adam; Park, Jongwan; McElroy, Austin B.; Estrada, Arnold D.; Fish, Scott; Beaman, Joseph J.; Milner, Thomas E.

2018-04-01

Selective laser sintering (SLS) is an efficient process in additive manufacturing that enables rapid part production from computer-based designs. However, SLS is limited by its notable lack of in situ process monitoring when compared with other manufacturing processes. We report the incorporation of optical coherence tomography (OCT) into an SLS system in detail and demonstrate access to surface and subsurface features. Video frame rate cross-sectional imaging reveals areas of sintering uniformity and areas of excessive heat error with high temporal resolution. We propose a set of image processing techniques for SLS process monitoring with OCT and report the limitations and obstacles for further OCT integration with SLS systems.

Positive control for cytotoxicity evaluation of dental vinyl polysiloxane impression materials using sodium lauryl sulfate.

PubMed

Kwon, Jae-Sung; Lee, Sang-Bae; Kim, Kwang-Mahn; Kim, Kyoung-Nam

2014-11-01

Vinyl polysiloxane (VPS) is elastomeric dental impression material which, despite having very few reports of adverse reactions, has shown high levels of cytotoxicity that is difficult to be interpreted without referencing to the positive control material. Therefore, in this study, positive control VPS was developed using sodium lauryl sulfate (SLS) for the reference of cytotoxicity test. The positive control VPS with SLS was formed with a different proportion of SLS (0, 1, 2, 4, 8 and 16 wt%) added to the base. The cytotoxicity test was then carried out using the extractions or dilutions of the extractions from each of the test samples using murine fibroblast cells (L929). The final product of positive control VPS behaved similar to commercially available VPS; being initially liquid-like and then becoming rubber-like. Ion chromatography showed that the level of SLS released from the product increased as the proportion of added SLS increased, consequently resulting in an increased level of cytotoxicity. Also, the commercially available VPS was less cytotoxic than the positive control VPS with more or equal to 2 wt% of SLS. However, even the VPS with the highest SLS (16 wt%) did not cause oral mucosa irritation during the animal study. The positive control VPS was successfully produced using SLS, which will be useful in terms of providing references during in vitro cytotoxicity testing.

Sodium Lauryl Sulfate Increases the Efficacy of a Topical Formulation of Foscarnet against Herpes Simplex Virus Type 1 Cutaneous Lesions in Mice

PubMed Central

Piret, Jocelyne; Désormeaux, André; Cormier, Hélène; Lamontagne, Julie; Gourde, Pierrette; Juhász, Julianna; Bergeron, Michel G.

2000-01-01

The influence of sodium lauryl sulfate (SLS) on the efficacies of topical gel formulations of foscarnet against herpes simplex virus type 1 (HSV-1) cutaneous infection has been evaluated in mice. A single application of the gel formulation containing 3% foscarnet given 24 h postinfection exerted only a modest effect on the development of herpetic skin lesions. Of prime interest, the addition of 5% SLS to this gel formulation markedly reduced the mean lesion score. The improved efficacy of the foscarnet formulation containing SLS could be attributed to an increased penetration of the antiviral agent into the epidermis. In vitro, SLS decreased in a concentration-dependent manner the infectivities of herpesviruses for Vero cells. SLS also inhibited the HSV-1 strain F-induced cytopathic effect. Combinations of foscarnet and SLS resulted in subsynergistic to subantagonistic effects, depending on the concentration used. Foscarnet in phosphate-buffered saline decreased in a dose-dependent manner the viability of cultured human skin fibroblasts. This toxic effect was markedly decreased when foscarnet was incorporated into the polymer matrix. The presence of SLS in the gel formulations did not alter the viabilities of these cells. The use of gel formulations containing foscarnet and SLS could represent an attractive approach to the treatment of herpetic mucocutaneous lesions, especially those caused by acyclovir-resistant strains. PMID:10952566

Application of the Aqueous Porous Pathway Model to Quantify the Effect of Sodium Lauryl Sulfate on Ultrasound-Induced Skin Structural Perturbation

PubMed Central

Polat, Baris E.; Seto, Jennifer E.; Blankschtein, Daniel; Langer, Robert

2011-01-01

This study investigated the effect of sodium lauryl sulfate (SLS) on skin structural perturbation when utilized simultaneously with low-frequency sonophoresis (LFS). Pig full-thickness skin (FTS) and pig split-thickness skin (STS) treated with LFS/SLS and LFS were analyzed in the context of the aqueous porous pathway model to quantify skin perturbation through changes in skin pore radius and porosity-to-tortuosity ratio (ε/τ). In addition, skin treatment times required to attain specific levels of skin electrical resistivity were analyzed to draw conclusions about the effect of SLS on reproducibility and predictability of skin perturbation. We found that LFS/SLS-treated FTS, LFS/SLS-treated STS, and LFS-treated FTS exhibited similar skin perturbation. However, LFS-treated STS exhibited significantly higher skin perturbation, suggesting greater structural changes to the less robust STS induced by the purely physical enhancement mechanism of LFS. Evaluation of ε/τ values revealed that LFS/SLS-treated FTS and STS have similar transport pathways, while LFS-treated FTS and STS have lower ε/τ values. In addition, LFS/SLS treatment times were much shorter than LFS treatment times for both FTS and STS. Moreover, the simultaneous use of SLS and LFS not only results in synergistic enhancement, as reflected in the shorter skin treatment times, but also in more predictable and reproducible skin perturbation. PMID:20963845

Skin penetration behaviour of sesquiterpene lactones from different Arnica preparations using a validated GC-MSD method.

PubMed

Wagner, Steffen; Merfort, Irmgard

2007-01-04

Preparations of Arnica montana L. are widely used for the topical treatment of inflammatory diseases. The anti-inflammatory activity is mainly attributed to their sesquiterpene lactones (SLs) from the helenalin and 11alpha,13-dihydrohelenalin type. To study the penetration kinetics of SLs in Arnica preparations, a stripping method with adhesive tape and pig skin as a model was used. For the determination of SLs in the stripped layers of the stratum corneum (SC), a gas chromatography/mass spectrometry method was developed and validated. Thereby the amount of helenalin derivatives was calculated as helenalin isobutyrate, and 11alpha,13-dihydrohelenalin derivatives as 11alpha,13-dihydrohelenalin methacrylate. This GC-MSD method is suitable also to determine low amounts of SLs in Arnica preparations. The penetration behaviour of one gel preparation and two ointment preparations was investigated. The SLs of all preparations show a comparable penetration in and a permeation through the stratum corneum, the uppermost part of the skin. Interestingly, the gel preparation showed a decrease of the penetration rate over 4h, whereas the penetration rate of ointments kept constant over time. Moreover, we could demonstrate that the totally penetrated amount of SLs only depends on the kind of the formulation and of the SLs-content in the formulation but not on the SLs composition or on the used extraction agent.

Cytotoxic 1-deoxysphingolipids are metabolized by a cytochrome P450-dependent pathway.

PubMed

Alecu, Irina; Othman, Alaa; Penno, Anke; Saied, Essa M; Arenz, Christoph; von Eckardstein, Arnold; Hornemann, Thorsten

2017-01-01

The 1-deoxysphingolipids (1-deoxySLs) are atypical sphingolipids (SLs) that are formed when serine palmitoyltransferase condenses palmitoyl-CoA with alanine instead of serine during SL synthesis. The 1-deoxySLs are toxic to neurons and pancreatic β-cells. Pathologically elevated 1-deoxySLs cause the inherited neuropathy, hereditary sensory autonomic neuropathy type 1 (HSAN1), and are also found in T2D. Diabetic sensory polyneuropathy (DSN) and HSAN1 are clinically very similar, suggesting that 1-deoxySLs may be implicated in both pathologies. The 1-deoxySLs are considered to be dead-end metabolites, as they lack the C1-hydroxyl group, which is essential for the canonical degradation of SLs. Here, we report a previously unknown metabolic pathway, which is capable of degrading 1-deoxySLs. Using a variety of metabolic labeling approaches and high-resolution high-accuracy MS, we identified eight 1-deoxySL downstream metabolites, which appear to be formed by cytochrome P450 (CYP)4F enzymes. Comprehensive inhibition and induction of CYP4F enzymes blocked and stimulated, respectively, the formation of the downstream metabolites. Consequently, CYP4F enzymes might be novel therapeutic targets for the treatment of HSAN1 and DSN, as well as for the prevention of T2D. Copyright © 2017 by the American Society for Biochemistry and Molecular Biology, Inc.

Production characteristics of the "higher plants-soil-like substrate" system as an element of the bioregenerative life support system

NASA Astrophysics Data System (ADS)

Velichko, V. V.; Tikhomirov, A. A.; Ushakova, S. A.; Tikhomirova, N. A.; Shihov, V. N.; Tirranen, L. S.; Gribovskaya, I. A.

2013-01-01

The study addresses the possibility of long-duration operation of a higher plant conveyor, using a soil-like substrate (SLS) as the root zone. Chufa (Cyperus esculentus L.), radish (Raphanus sativus L.), and lettuce (Lactuca sativa L.) were used as study material. A chufa community consisting of 4 age groups and radish and lettuce communities consisting of 2 age groups were irrigated with a nutrient solution, which contained mineral elements extracted from the SLS. After each harvest, inedible biomass of the harvested plants and inedible biomasses of wheat and saltwort were added to the SLS. The amounts of the inedible biomasses of wheat and saltwort to be added to the SLS were determined based on the nitrogen content of the edible mass of harvested plants. CO2 concentration in the growth chamber was maintained within the range of 1100-1700 ppm. The results of the study show that higher plants can be grown quite successfully using the proposed process of plant waste utilization in the SLS. The addition of chufa inedible biomass to the SLS resulted in species-specific inhibition of growth of both cultivated crops and microorganisms in the "higher plants - SLS" system. There were certain differences between the amounts of some mineral elements removed from the SLS with the harvested edible biomass and those added to it with the inedible biomasses of wheat and saltwort.

Physiological and behavioural effects of intradermal injection of sodium lauryl sulfate as an alternative to mulesing in lambs.

PubMed

Colditz, I G; Paull, D R; Lee, C; Fisher, A D

2010-12-01

To assess the effects on physiology and behaviour of intradermal injection of sodium lauryl sulfate (SLS) as an alternative to mulesing. Three groups of Merino lambs were studied: Control (n = 10), SLS (n = 11) and Mulesed (n = 11). The SLS group received SLS (7% w/v) and benzyl alcohol (20 mg/mL) in phosphate buffer, and the Mulesed group received 6 mL topical local anaesthetic as a wound dressing. Haematology, cortisol, beta-endorphin and haptoglobin concentrations, rectal temperatures, body weight and behaviours were monitored for up to 42 days post treatments. SLS treatment induced mild swelling followed by thin scab formation. Fever (>40°C) was observed at 12 and 24 h, cortisol concentration was elevated on days 1 and 2, haptoglobin concentration was highly elevated on days 2-7, white blood cell count was elevated on days 2 and 4 post treatment, but average daily gain was not affected. Fever at 12 h was significantly higher in the SLS than in the Mulesed group, whereas maximum temperature, temperature area under the curve (AUC), occurrence of fever, cortisol profile, cortisol AUC, white blood cell counts and haptoglobin concentrations until day 7 were comparable. The behaviours of normal standing, total standing and total lying were modified for 2 days by SLS treatment, but changes were less marked and of shorter duration than in the Mulesed group. On day 1, the SLS group spent <5% of time in total abnormal behaviours compared with 18% in the Mulesed group. The SLS group tended to spend more time in abnormal behaviours on day 1 than the Controls. The behaviour of the SLS group was similar to that of the unmulesed Controls and their physiological responses were intermediate between the Mulesed lambs receiving post-surgical analgesia and the Controls. © 2010 CSIRO. Australian Veterinary Journal © 2010 Australian Veterinary Association.

The Space Launch System and Missions to the Outer Solar System

NASA Astrophysics Data System (ADS)

Klaus, Kurt K.; Post, Kevin

2015-11-01

Introduction: America’s heavy lift launch vehicle, the Space Launch System, enables a variety of planetary science missions. The SLS can be used for most, if not all, of the National Research Council’s Planetary Science Decadal Survey missions to the outer planets. The SLS performance enables larger payloads and faster travel times with reduced operational complexity.Europa Clipper: Our analysis shows that a launch on the SLS would shorten the Clipper mission travel time by more than four years over earlier mission concept studies.Jupiter Trojan Tour and Rendezvous: Our mission concept replaces Advanced Stirling Radioisotope Generators (ASRGs) in the original design with solar arrays. The SLS capability offers many more target opportunities.Comet Surface Sample Return: Although in our mission concept, the SLS launches later than the NRC mission study (November 2022 instead of the original launch date of January 2021), it reduces the total mission time, including sample return, by two years.Saturn Apmospheric Entry Probe: Though Saturn arrivial time remains the same in our concept as the arrival date in the NRC study (2034), launching on the SLS shortens the mission travel time by three years with a direct ballistic trajectory.Uranus Orbiter with Probes: The SLS shortens travel time for an Uranus mission by four years with a Jupiter swing-by trajectory. It removes the need for a solar electric propulsion (SEP) stage used in the NRC mission concept study.Other SLS Science Mission Candidates: Two other mission concepts we are investigating that may be of interest to this community are the Advanced Technology Large Aperature Space Telescope (ATLAST) and the Interstellar Explorer also referred to as the Interstellar Probe.Summary: The first launch of the SLS is scheduled for 2018 followed by the first human launch in 2021. The SLS in its evolving configurations will enable a broad range of exploration missions which will serve to recapture the enthusiasm and commitment that permeated the planetary exploration community during the early years of robotic exploration.

Evaluation of implantation-disordering of (InGa)As/GaAs strained-layer superlattices

NASA Astrophysics Data System (ADS)

Myers, D. R.; Barnes, C. E.; Arnold, G. W.; Dawson, L. R.; Biefeld, R. M.; Zipperian, T. E.; Gourley, P. L.; Fritz, I. J.

The optical and transport properties of InO 2GaO 8As/GaAs strained-layer superlattices (SLS's) which were implanted either with 5 x 10 to the 15th power, 250 keV Zn(+) or with 5 x 10 to 14th power/square cm/cm(2), 70 keV Be(+) and annealed under an arsenic overpressure at 600 (0) C were examined. For both cases, electrical activation in the implantation-doped regions equalled that of similar implants and anneals in bulk GaAs, even though the Be implant retained the SLS structure, while the Zn implant intermixed the SLS layers to produce an alloy semiconductor of the average SLS composition. Photoluminescence intensities in the annealed implanted regions were significantly reduced from that of virgin material, apparently due to residual implant damage. Diodes formed from both the Be- and the Zn-implanted SLS' produced electroluminescence internsity comparable to that of grown-junction SLS diodes in the same chemical system, despite the implantation processing and the potential for vertical lattice mismatch in the Zn-disordered SLS device. These results indicate that Zn-disordering can be as useful for strained-layer superlattices as in lattice-matched systems.

Light Scattering Study of Mixed Micelles Made from Elastin-Like Polypeptide Linear Chains and Trimers

NASA Astrophysics Data System (ADS)

Terrano, Daniel; Tsuper, Ilona; Maraschky, Adam; Holland, Nolan; Streletzky, Kiril

Temperature sensitive nanoparticles were generated from a construct (H20F) of three chains of elastin-like polypeptides (ELP) linked to a negatively charged foldon domain. This ELP system was mixed at different ratios with linear chains of ELP (H40L) which lacks the foldon domain. The mixed system is soluble at room temperature and at a transition temperature (Tt) will form swollen micelles with the hydrophobic linear chains hidden inside. This system was studied using depolarized dynamic light scattering (DDLS) and static light scattering (SLS) to determine the size, shape, and internal structure of the mixed micelles. The mixed micelle in equal parts of H20F and H40L show a constant apparent hydrodynamic radius of 40-45 nm at the concentration window from 25:25 to 60:60 uM (1:1 ratio). At a fixed 50 uM concentration of the H20F, varying H40L concentration from 5 to 80 uM resulted in a linear growth in the hydrodynamic radius from about 11 to about 62 nm, along with a 1000-fold increase in VH signal. A possible simple model explaining the growth of the swollen micelles is considered. Lastly, the VH signal can indicate elongation in the geometry of the particle or could possibly be a result from anisotropic properties from the core of the micelle. SLS was used to study the molecular weight, and the radius of gyration of the micelle to help identify the structure and morphology of mixed micelles and the tangible cause of the VH signal.

Scintillometer measurements above the urban area of London

NASA Astrophysics Data System (ADS)

Pauscher, Lukas; Salmond, Jennifer; Grimmond, C. S. B.; Foken, Thomas

2010-05-01

The spatial heterogeneity of urban surfaces presents a particular challenge to the measurement of turbulent fluxes. This is particularly true close to the urban surface (in the roughness sub-layer (RSL)) where the mosaic of roof top and street canyon surfaces present a complex three dimensional source area. Scintillometery, which offers the ability to make path-averaged measurements of turbulent fluxes of heat and momentum, provides an alternative approach to obtaining more spatially representative data sets in the RSL. In this study three Scintec small aperture scintillometers (SLS 20) were used to measure the sensible heat flux (QH) at a densely built up site at Strand Campus, King's College London, UK. Two different surfaces (courtyard and rooftop) characteristic of the urban environment were investigated simultaneously. One of the SLS was aligned just atop a courtyard (z/zH= 0.9), while the other two were set up in two different heights (z/zH= 1 and z/zH= 1.25) above a rooftop line. Where zH is the mean building height and z is the measurement height above ground level. Special consideration was given to the estimation of the displacement height and the influence of the Monin-Obukov function used for the analysis. To estimate the contribution of the different surface types to the observed fluxes a footprint analysis was carried out for the two rooftop SLS and the eddy covariance system. Fluxes from the two SLS above the rooftop generally agreed well with each other and exhibited a pronounced diurnal cycle. They also showed similar patterns and magnitudes as those measured by an eddy covariance system located close by. In contrast, diurnal flux patterns derived from the measurements atop the courtyard showed marked differences, especially during day time when fluxes often remained smaller.

Self-organizing maps of molecular descriptors for sesquiterpene lactones and their application to the chemotaxonomy of the Asteraceae family.

PubMed

Scotti, Marcus T; Emerenciano, Vicente; Ferreira, Marcelo J P; Scotti, Luciana; Stefani, Ricardo; da Silva, Marcelo S; Mendonça Junior, Francisco Jaime B

2012-04-20

The Asteraceae, one of the largest families among angiosperms, is chemically characterised by the production of sesquiterpene lactones (SLs). A total of 1,111 SLs, which were extracted from 658 species, 161 genera, 63 subtribes and 15 tribes of Asteraceae, were represented and registered in two dimensions in the SISTEMATX, an in-house software system, and were associated with their botanical sources. The respective 11 block of descriptors: Constitutional, Functional groups, BCUT, Atom-centred, 2D autocorrelations, Topological, Geometrical, RDF, 3D-MoRSE, GETAWAY and WHIM were used as input data to separate the botanical occurrences through self-organising maps. Maps that were generated with each descriptor divided the Asteraceae tribes, with total index values between 66.7% and 83.6%. The analysis of the results shows evident similarities among the Heliantheae, Helenieae and Eupatorieae tribes as well as between the Anthemideae and Inuleae tribes. Those observations are in agreement with systematic classifications that were proposed by Bremer, which use mainly morphological and molecular data, therefore chemical markers partially corroborate with these classifications. The results demonstrate that the atom-centred and RDF descriptors can be used as a tool for taxonomic classification in low hierarchical levels, such as tribes. Descriptors obtained through fragments or by the two-dimensional representation of the SL structures were sufficient to obtain significant results, and better results were not achieved by using descriptors derived from three-dimensional representations of SLs. Such models based on physico-chemical properties can project new design SLs, similar structures from literature or even unreported structures in two-dimensional chemical space. Therefore, the generated SOMs can predict the most probable tribe where a biologically active molecule can be found according Bremer classification.

Breast Milk-Acquired Cytomegalovirus Infection and Disease in Very Low Birth Weight and Premature Infants

PubMed Central

Lanzieri, Tatiana M.; Dollard, Sheila C.; Josephson, Cassandra D.; Schmid, D. Scott; Bialek, Stephanie R.

2016-01-01

Introduction Very low birth weight (VLBW) and premature infants are at risk of developing postnatal cytomegalovirus (CMV) disease, including CMV-related sepsis-like syndrome (CMV-SLS). Estimates of breast milk-acquired CMV infection and disease among these infants in the United States are lacking. Methods We performed a systematic review and meta-analysis to estimate the pooled proportions (and 95% confidence intervals) of VLBW and premature infants born to CMV-seropositive women with breast milk-acquired CMV infection and CMV-SLS. We combined these proportions with population-based rates of CMV seropositivity, breast milk feeding, VLBW and prematurity to estimate annual rates of breast milk-acquired CMV infection and CMV-SLS in the United States. Results In our meta-analysis, among 299 infants fed untreated breast milk, we estimated 19% (11%–32%) acquired CMV infection and 4% (2%–7%) developed CMV-SLS. Assuming these proportions, we estimated a rate of breast milk-acquired CMV infection among VLBW and premature infants in the United States of 6.5% (3.7%–10.9%) and 1.4% (0.7%–2.4%) of CMV-SLS, corresponding to 600 infants with CMV-SLS in 2008. Among 212 infants fed frozen breast milk, our meta-analysis proportions were 13% (7%–24%) for infection and 5% (2%–12%) for CMV-SLS, yielding slightly lower rates of breast milk-acquired CMV infection (4.4%; 2.4%–6.8%) but similar rates of CMV-SLS (1.7%; 0.7%–4.1%). Conclusions Breast milk-acquired CMV infection presenting with CMV-SLS is relatively rare. Prospective studies to better define the burden of disease are needed to refine guidelines for feeding breast milk from CMV-seropositive mothers to VLBW and premature infants. PMID:23713111

Growth and characterization of In1-xGaxAs/InAs0.65Sb0.35 strained layer superlattice infrared detectors

NASA Astrophysics Data System (ADS)

Ariyawansa, G.; Duran, J. M.; Reyner, C. J.; Steenbergen, E. H.; Yoon, N.; Wasserman, D.; Scheihing, J. E.

2017-02-01

Type-II strained layer superlattices (SLS) are an active research topic in the infrared detector community and applications for SLS detectors continue to grow. SLS detector technology has already reached the commercial market due to improvements in material quality, device design, and device fabrication. Despite this progress, the optimal superlattice design has not been established, and at various times has been believed to be InAs/GaSb, InAs/InGaSb, or InAs/InAsSb. Building on these, we investigate the properties of a new mid-wave infrared SLS material: InGaAs/InAsSb SLS. The ternary InGaAs/InAsSb SLS has three main advantages over other SLS designs: greater support for strain compensation, enhanced absorption due to increased electron-hole wavefunction overlap, and improved vertical hole mobility due to reduced hole effective mass. Here, we compare three ternary SLSs, with approximately the same bandgap (0.240 eV at 150 K), comprised of Ga fractions of 5%, 10%, and 20% to a reference sample with 0% Ga. Enhanced absorption is both theoretically predicted and experimentally realized. Furthermore, the characteristics of ternary SLS infrared detectors based on an nBn architecture are reported and exhibit nearly state-of-the-art dark current performance with minimal growth optimization. We report standard material and device characterization information, including dark current and external quantum efficiency, and provide further analysis that indicates improved quantum efficiency and vertical hole mobility. Finally, a 320×256 focal plane array built based on the In0.8Ga0.2As/InAs0.65Sb0.35 SLS design is demonstrated with promising performance.

Breast milk-acquired cytomegalovirus infection and disease in VLBW and premature infants.

PubMed

Lanzieri, Tatiana M; Dollard, Sheila C; Josephson, Cassandra D; Schmid, D Scott; Bialek, Stephanie R

2013-06-01

Very low birth weight (VLBW) and premature infants are at risk for developing postnatal cytomegalovirus (CMV) disease, including CMV-related sepsis-like syndrome (CMV-SLS) for which estimates [corrected] in the United States are lacking. We performed a systematic review and meta-analysis to estimate the pooled proportions (and 95% confidence intervals) of VLBW and premature infants born to CMV-seropositive women with breast milk-acquired CMV infection and CMV-SLS. We combined these proportions with population-based rates of CMV seropositivity, breast milk feeding, VLBW, and prematurity to estimate annual rates of breast milk-acquired CMV infection and CMV-SLS in the United States. In our meta-analysis, among 299 infants fed untreated breast milk, we estimated 19% (11%-32%) acquired CMV infection and 4% (2%-7%) developed CMV-SLS. Assuming these proportions, we estimated a rate of breast milk-acquired CMV infection among VLBW and premature infants in the United States of 6.5% (3.7%-10.9%) and 1.4% (0.7%-2.4%) of CMV-SLS, corresponding to 600 infants with CMV-SLS in 2008. Among 212 infants fed frozen breast milk, our meta-analysis proportions were 13% (7%-24%) for infection and 5% (2%-12%) for CMV-SLS, yielding slightly lower rates of breast milk-acquired CMV infection (4.4%; 2.4%-8.2%) but similar rates of CMV-SLS (1.7%; 0.7%-4.1%). Breast milk-acquired CMV infection presenting with CMV-SLS is relatively rare. Prospective studies to better define the burden of disease are needed to refine guidelines for feeding breast milk from CMV-seropositive mothers to VLBW and premature infants.

Genetic Locus for Streptolysin S Production by Group A Streptococcus

PubMed Central

Nizet, Victor; Beall, Bernard; Bast, Darrin J.; Datta, Vivekananda; Kilburn, Laurie; Low, Donald E.; De Azavedo, Joyce C. S.

2000-01-01

Group A streptococcus (GAS) is an important human pathogen that causes pharyngitis and invasive infections, including necrotizing fasciitis. Streptolysin S (SLS) is the cytolytic factor that creates the zone of beta-hemolysis surrounding GAS colonies grown on blood agar. We recently reported the discovery of a potential genetic determinant involved in SLS production, sagA, encoding a small peptide of 53 amino acids (S. D. Betschel, S. M. Borgia, N. L. Barg, D. E. Low, and J. C. De Azavedo, Infect. Immun. 66:1671–1679, 1998). Using transposon mutagenesis, chromosomal walking steps, and data from the GAS genome sequencing project (www.genome.ou.edu/strep.html), we have now identified a contiguous nine-gene locus (sagA to sagI) involved in SLS production. The sag locus is conserved among GAS strains regardless of M protein type. Targeted plasmid integrational mutagenesis of each gene in the sag operon resulted in an SLS-negative phenotype. Targeted integrations (i) upstream of the sagA promoter and (ii) downstream of a terminator sequence after sagI did not affect SLS production, establishing the functional boundaries of the operon. A rho-independent terminator sequence between sagA and sagB appears to regulate the amount of sagA transcript produced versus transcript for the entire operon. Reintroduction of the nine-gene sag locus on a plasmid vector restored SLS activity to the nonhemolytic sagA knockout mutant. Finally, heterologous expression of the intact sag operon conferred the SLS beta-hemolytic phenotype to the nonhemolytic Lactococcus lactis. We conclude that gene products of the GAS sag operon are both necessary and sufficient for SLS production. Sequence homologies of sag operon gene products suggest that SLS is related to the bacteriocin family of microbial toxins. PMID:10858242

Space Launch System (SLS) Program Overview NASA Research Announcement (NRA) Advanced Booster (AB) Engineering Demonstration and Risk Reduction (EDRR) Industry Day

NASA Technical Reports Server (NTRS)

May, Todd A.

2011-01-01

SLS is a national capability that empowers entirely new exploration for missions of national importance. Program key tenets are safety, affordability, and sustainability. SLS builds on a solid foundation of experience and current capacities to enable a timely initial capability and evolve to a flexible heavy-lift capability through competitive opportunities: (1) Reduce risks leading to an affordable Advanced Booster that meets the evolved capabilities of SLS (2) Enable competition by mitigating targeted Advanced Booster risks to enhance SLS affordability and performance The road ahead promises to be an exciting journey for present and future generations, and we look forward to working with you to continue America fs space exploration.

Human and Environmental Toxicity of Sodium Lauryl Sulfate (SLS): Evidence for Safe Use in Household Cleaning Products.

PubMed

Bondi, Cara Am; Marks, Julia L; Wroblewski, Lauren B; Raatikainen, Heidi S; Lenox, Shannon R; Gebhardt, Kay E

2015-01-01

Environmental chemical exposure is a major concern for consumers of packaged goods. The complexity of chemical nomenclature and wide availability of scientific research provide detailed information but lends itself to misinterpretation by the lay person. For the surfactant sodium lauryl sulfate (SLS), this has resulted in a misunderstanding of the environmental health impact of the chemical and statements in the media that are not scientifically supported. This review demonstrates how scientific works can be misinterpreted and used in a manner that was not intended by the authors, while simultaneously providing insight into the true environmental health impact of SLS. SLS is an anionic surfactant commonly used in consumer household cleaning products. For decades, this chemical has been developing a negative reputation with consumers because of inaccurate interpretations of the scientific literature and confusion between SLS and chemicals with similar names. Here, we review the human and environmental toxicity profiles of SLS and demonstrate that it is safe for use in consumer household cleaning products.

Surface-coated fly ash reinforced biodegradable poly(vinyl alcohol) composite films: part 2-analysis and characterization

NASA Astrophysics Data System (ADS)

Nath, D. C. D.; Bandyopadhyay, S.; Campbell, J.; Yu, A.; Blackburn, D.; White, C.

2010-12-01

Composite films of poly(vinyl alcohol) (PVA) reinforced with 5, 10, 15, 20 and 25 wt.% surface-coated fly ash by surfactant, sodium lauryl sulphate (SLS-FA) along with 1 wt.% cross-linking agent, glutaraldehyde (GLA) were prepared by aqueous casting method. The tensile strengths of the composite films were increased proportionally with the addition of SLS-FA. The maximum 75% higher strength of the composite with 20 wt.% was achieved compared to that of neat PVA. The modulus of the composites was also increased proportionally with SLS-FA and the maximum 218% reached in composite with 20 wt.%, but the strain at break was decreased with addition of SLS-FA. Changes in FTIR spectra reflect the chemical and/or physical bonding in the ternary PVA, SLS-FA and GLA component systems. In the study of surface morphology, the connectivity was visualized in SEM images along with interstitial voids. The films with SLS-FA show 53% smoother surface calculated with AFM compared to unmodified FA composite films.

Human and Environmental Toxicity of Sodium Lauryl Sulfate (SLS): Evidence for Safe Use in Household Cleaning Products

PubMed Central

Bondi, Cara AM; Marks, Julia L; Wroblewski, Lauren B; Raatikainen, Heidi S; Lenox, Shannon R; Gebhardt, Kay E

2015-01-01

Environmental chemical exposure is a major concern for consumers of packaged goods. The complexity of chemical nomenclature and wide availability of scientific research provide detailed information but lends itself to misinterpretation by the lay person. For the surfactant sodium lauryl sulfate (SLS), this has resulted in a misunderstanding of the environmental health impact of the chemical and statements in the media that are not scientifically supported. This review demonstrates how scientific works can be misinterpreted and used in a manner that was not intended by the authors, while simultaneously providing insight into the true environmental health impact of SLS. SLS is an anionic surfactant commonly used in consumer household cleaning products. For decades, this chemical has been developing a negative reputation with consumers because of inaccurate interpretations of the scientific literature and confusion between SLS and chemicals with similar names. Here, we review the human and environmental toxicity profiles of SLS and demonstrate that it is safe for use in consumer household cleaning products. PMID:26617461

Strain modulation-enhanced Mg acceptor activation efficiency of Al0.14Ga0.86N/GaN superlattices with AlN interlayer

NASA Astrophysics Data System (ADS)

Wang, Lei; Li, Rui; Li, Ding; Liu, Ningyang; Liu, Lei; Chen, Weihua; Wang, Cunda; Yang, Zhijian; Hu, Xiaodong

2010-02-01

AlN layer was grown as interlayer between undoped GaN and Mg doped Al0.14Ga0.86N/GaN superlattices (SLs) epilayer to modulate the strain distribution between Al0.14Ga0.86N barrier and GaN well layers in SLs sample. Strain relaxation was observed in the SLs sample with AlN interlayer by x-ray diffraction reciprocal space mapping method. The measured hole concentration of SLs sample with AlN interlayer at room temperature was over 1.6×1018 cm-3 but that was only 6.6×1016 cm-3 obtained in SLs sample without AlN interlayer. Variable temperature Hall-effect measurement showed that the acceptor activation energy decreased from 150 to 70 meV after inserting the AlN layer, which indicated that the strain modulation of SLs induced by AlN interlayer was beneficial to the Mg acceptor activation and hole concentration enhancement.

Closure of mass exchange under use of a vegetable conveyer cultivated on a neutral and soil-like substrates as applied to BLSS

NASA Astrophysics Data System (ADS)

Velitchko, Vladimir; Tikhomirov, Alexander; Ushakova, Sofya

To increase a closure level of mass exchange processes in bioregenerative life support systems (BLSS) including a human a technology of plants cultivation on a soil-like substrate (SLS) consisting in a gradual decomposition of inedible plants biomass under its addition in the SLS was developed at the Institute of Biophysics SB RAS (Russia). In the given work the effect of periodical introduction of inedible plant biomass in the SLS on plants photosynthetic productivity and on the closure of mass exchange has been analyzed. Thereupon CO2 gas exchange and the certain vegetables' productivity under their cultivation in a conveyor regime on the SLS and on a neutral substrate with reference to the closure of mass exchange processes in BLSS have been studied in this work. The vegetables Raphanus sativus L., Brassica caulorapa L. Daucus carota L. and Beta vulgaris L. being prospective plantsrepresentatives of the BLSS phototrophic unit were taken as the research objects. The SLS was taken as an experiment substrate and an expanded clay aggregate as the control. The changeable Knop solution was used for the control, and an irrigation solution with the SLS extract was used for the experiment. Rapidity dynamics of CO2 consumption showed sharp distinctions of the ‘plants-SLS' system from the ‘plantsexpanded clay aggregate' system connected with the oxidation processes coursing in the SLS. The intensity of CO2 evolution from the SLS on average was 70% of the total plants conveyor's respiration. Thus a balance between the system's respiration and photosynthesis was often determined by the processes coursing in the SLS. Here the sharp CO2 evolution was recorded after introduction of the plants inedible biomass in the SLS. That peak was gradually coming down during 10-14 days after the beginning of every cycle of plants cultivation that was connected with intensification of plants photosynthesis and drop of decomposition intensity of the biomass introduced. Comparative estimation of plants productivity in the control and in the experiment showed that the plants grown on the SLS had amassed less of total (on 40%) and edible (on 26%) dry biomass in comparison with the control. Probably that decrease in productivity was connected with unbalance on mineral elements under introduction of mineralized straw in the amount equivalent to the mass of the plants edible part. Cultivated on the SLS the vegetable conveyor on average gave 80 g*m-2 *day-1 of dry edible biomass that approximately amounted 13% of a total daily vegetative ration of a human. The use resources of the plants cultivation methods on different substrates under study depending on the requirements to a closure level of mass exchange processes in BLSS has been discussed.

Application of the aqueous porous pathway model to quantify the effect of sodium lauryl sulfate on ultrasound-induced skin structural perturbation.

PubMed

Polat, Baris E; Seto, Jennifer E; Blankschtein, Daniel; Langer, Robert

2011-04-01

This study investigated the effect of sodium lauryl sulfate (SLS) on skin structural perturbation when utilized simultaneously with low-frequency sonophoresis (LFS). Pig full-thickness skin (FTS) and pig split-thickness skin (STS) treated with LFS/SLS and LFS were analyzed in the context of the aqueous porous pathway model to quantify skin perturbation through changes in skin pore radius and porosity-to-tortuosity ratio (ε/τ). In addition, skin treatment times required to attain specific levels of skin electrical resistivity were analyzed to draw conclusions about the effect of SLS on reproducibility and predictability of skin perturbation. We found that LFS/SLS-treated FTS, LFS/SLS-treated STS, and LFS-treated FTS exhibited similar skin perturbation. However, LFS-treated STS exhibited significantly higher skin perturbation, suggesting greater structural changes to the less robust STS induced by the purely physical enhancement mechanism of LFS. Evaluation of ε/τ values revealed that LFS/SLS-treated FTS and STS have similar transport pathways, whereas LFS-treated FTS and STS have lower ε/τ values. In addition, LFS/SLS treatment times were much shorter than LFS treatment times for both FTS and STS. Moreover, the simultaneous use of SLS and LFS not only results in synergistic enhancement, as reflected in the shorter skin treatment times, but also in more predictable and reproducible skin perturbation. Copyright © 2010 Wiley-Liss, Inc.

Forward Skirt Structural Testing on the Space Launch System (SLS) Program

NASA Technical Reports Server (NTRS)

Lohrer, Joe; Wright, R. D.

2016-01-01

Introduction: (a) Structural testing was performed to evaluate Space Shuttle heritage forward skirts for use on the Space Launch System (SLS) program, (b) Testing was required because SLS loads are approximately 35% greater than shuttle loads; and (c) Two forwards skirts were tested to failure.

Space Launch System—New Exterior Markings (2017 Animation)

NASA Image and Video Library

2017-06-13

Animation depicting NASA’s Space Launch System, the world's most powerful rocket for a new era of human exploration in deep space. Black-and-white checkerboard targets on the exterior of the SLS heavy-lift rocket will enable photogrammetrists to measure critical distances during spaceflight, including booster separation from the core stage. With its unprecedented capabilities, SLS will launch astronauts in the agency’s Orion spacecraft on missions to explore multiple, deep-space destinations, including Mars. For more information on SLS, visit https://www.nasa.gov/exploration/systems/sls

Assessment and Verification of SLS Block 1-B Exploration Upper Stage and Stage Disposal Performance

NASA Technical Reports Server (NTRS)

Patrick, Sean; Oliver, T. Emerson; Anzalone, Evan J.

2018-01-01

Delta-v allocation to correct for insertion errors caused by state uncertainty is one of the key performance requirements imposed on the SLS Navigation System. Additionally, SLS mission requirements include the need for the Exploration Up-per Stage (EUS) to be disposed of successfully. To assess these requirements, the SLS navigation team has developed and implemented a series of analysis methods. Here the authors detail the Delta-Delta-V approach to assessing delta-v allocation as well as the EUS disposal optimization approach.

Vice President Pence Visits SLS Engineering Test Facility

NASA Image and Video Library

2017-09-25

The Vice President toured the SLS engineering facility where the engine section of the rocket’s massive core stage is undergoing a major stress test. The rocket’s four RS-25 engines and the two solid rocket boosters that attach to the SLS engine section will produce more than 8 million pounds of thrust to launch the Orion spacecraft beyond low-Earth orbit. More than 3,000 measurements using sensors installed on the test section will help ensure the core stage for all SLS missions can withstand the extreme forces of flight.

IV&V Project Assessment Process Validation

NASA Technical Reports Server (NTRS)

Driskell, Stephen

2012-01-01

The Space Launch System (SLS) will launch NASA's Multi-Purpose Crew Vehicle (MPCV). This launch vehicle will provide American launch capability for human exploration and travelling beyond Earth orbit. SLS is designed to be flexible for crew or cargo missions. The first test flight is scheduled for December 2017. The SLS SRR/SDR provided insight into the project development life cycle. NASA IV&V ran the standard Risk Based Assessment and Portfolio Based Risk Assessment to identify analysis tasking for the SLS program. This presentation examines the SLS System Requirements Review/System Definition Review (SRR/SDR), IV&V findings for IV&V process validation correlation to/from the selected IV&V tasking and capabilities. It also provides a reusable IEEE 1012 scorecard for programmatic completeness across the software development life cycle.

SLS Trade Study 0058: Day of Launch (DOL) Wind Biasing

NASA Technical Reports Server (NTRS)

Decker, Ryan K.; Duffin, Paul; Hill, Ashley; Beck, Roger; Dukeman, Greg

2014-01-01

SLS heritage hardware and legacy designs have shown load exceedances at several locations during Design Analysis Cycles (DAC): MPCV Z bending moments; ICPS Electro-Mechanical Actuator (EMA) loads; Core Stage loads just downstream of Booster forward interface. SLS Buffet Loads Mitigation Task Team (BLMTT) tasked to study issue. Identified low frequency buffet load responses are a function of the vehicle's total angle of attack (AlphaTotal). SLS DOL Wind Biasing Trade team to analyze DOL wind biasing methods to limit maximum AlphaTotal in the M0.8 - 2.0 altitude region for EM-1 and EM-2 missions through investigating: Trajectory design process; Wind wavelength filtering options; Launch availability; DOL process to achieve shorter processing/uplink timeline. Trade Team consisted of personnel supporting SLS, MPCV, GSDO programs.

The Role of Strigolactones in Nutrient-Stress Responses in Plants

PubMed Central

Marzec, Marek; Muszynska, Aleksandra; Gruszka, Damian

2013-01-01

Strigolactones (SLs) are a new group of plant hormones, which have been intensively investigated during the last few years. The wide spectrum of SLs actions, including the regulation of shoot/root architecture, and the stimulation of the interactions between roots and fungi or bacteria, as well as the stimulation of germination of parasitic plants, indicates that this group of hormones may play an important role in the mechanisms that control soil exploration, and the root-mediated uptake of nutrients. Current studies have shown that SLs might be factors that have an influence on the plant response to a deficiency of macronutrients. Experimental data from the last four years have confirmed that the biosynthesis and exudation of SLs are increased under phosphorus and nitrogen deficiency. All these data suggest that SLs may regulate the complex response to nutrient stress, which include not only the modification of the plant developmental process, but also the cooperation with other organisms in order to minimize the effects of threats. In this paper the results of studies that indicate that SLs play an important role in the response to nutrient stress are reviewed and the consequences of the higher biosynthesis and exudation of SLs in response to phosphorus and nitrogen deficiency are discussed. PMID:23629665

NASA's Space Launch System: A Transformative Capability for Exploration

NASA Technical Reports Server (NTRS)

Robinson, Kimberly F.; Cook, Jerry; Hitt, David

2016-01-01

Currently making rapid progress toward first launch in 2018, NASA's exploration-class Space Launch System (SLS) represents a game-changing new spaceflight capability, enabling mission profiles that are currently impossible. Designed to launch human deep-space missions farther into space than ever before, the initial configuration of SLS will be able to deliver more than 70 metric tons of payload to low Earth orbit (LEO), and will send NASA's new Orion crew vehicle into lunar orbit. Plans call for the rocket to evolve on its second flight, via a new upper stage, to a more powerful configuration capable of lofting 105 tons to LEO or co-manifesting additional systems with Orion on launches to the lunar vicinity. Ultimately, SLS will evolve to a configuration capable of delivering more than 130 tons to LEO. SLS is a foundational asset for NASA's Journey to Mars, and has been recognized by the International Space Exploration Coordination Group as a key element for cooperative missions beyond LEO. In order to enable human deep-space exploration, SLS provides unrivaled mass, volume, and departure energy for payloads, offering numerous benefits for a variety of other missions. For robotic science probes to the outer solar system, for example, SLS can cut transit times to less than half that of currently available vehicles, producing earlier data return, enhancing iterative exploration, and reducing mission cost and risk. In the field of astrophysics, SLS' high payload volume, in the form of payload fairings with a diameter of up to 10 meters, creates the opportunity for launch of large-aperture telescopes providing an unprecedented look at our universe, and offers the ability to conduct crewed servicing missions to observatories stationed at locations beyond low Earth orbit. At the other end of the spectrum, SLS opens access to deep space for low-cost missions in the form of smallsats. The first launch of SLS will deliver beyond LEO 13 6-unit smallsat payloads, representing multiple disciplines, including three spacecraft competitively chosen through NASA's Centennial Challenges competition. Private organizations have also identified benefits of SLS for unique public-private partnerships. This paper will give an overview of SLS' capabilities and its current status, and discuss the vehicle's potential for human exploration of deep space and other game-changing utilization opportunities.

NASA's Space Launch System: A Transformative Capability for Exploration

NASA Technical Reports Server (NTRS)

Robinson, Kimberly F.; Cook, Jerry

2016-01-01

Currently making rapid progress toward first launch in 2018, NASA's exploration-class Space Launch System (SLS) represents a game-changing new spaceflight capability, enabling mission profiles that are currently impossible. Designed to launch human deep-space missions farther into space than ever before, the initial configuration of SLS will be able to deliver more than 70 metric tons of payload to low Earth orbit (LEO), and will send NASA's new Orion crew vehicle into lunar orbit. Plans call for the rocket to evolve on its second flight, via a new upper stage, to a more powerful configuration capable of lofting 105 t to LEO or comanifesting additional systems with Orion on launches to the lunar vicinity. Ultimately, SLS will evolve to a configuration capable of delivering more than 130 t to LEO. SLS is a foundational asset for NASA's Journey to Mars, and has been recognized by the International Space Exploration Coordination Group as a key element for cooperative missions beyond LEO. In order to enable human deep-space exploration, SLS provides unrivaled mass, volume, and departure energy for payloads, offering numerous benefits for a variety of other missions. For robotic science probes to the outer solar system, for example, SLS can cut transit times to less than half that of currently available vehicles, producing earlier data return, enhancing iterative exploration, and reducing mission cost and risk. In the field of astrophysics, SLS' high payload volume, in the form of payload fairings with a diameter of up to 10 meters, creates the opportunity for launch of large-aperture telescopes providing an unprecedented look at our universe, and offers the ability to conduct crewed servicing missions to observatories stationed at locations beyond low Earth orbit. At the other end of the spectrum, SLS opens access to deep space for low-cost missions in the form of smallsats. The first launch of SLS will deliver beyond LEO 13 6U smallsat payloads, representing multiple disciplines, including three spacecraft competitively chosen through NASA's Centennial Challenges competition. Private organizations have also identified benefits of SLS for unique public-private partnerships. This paper will give an overview of SLS' capabilities and its current status, and discuss the vehicle's potential for human exploration of deep space and other game-changing utilization opportunities.

NASA's Space Launch System: A New Opportunity for CubeSats

NASA Technical Reports Server (NTRS)

Hitt, David; Robinson, Kimberly F.; Creech, Stephen D.

2016-01-01

Designed for human exploration missions into deep space, NASA's Space Launch System (SLS) represents a new spaceflight infrastructure asset, enabling a wide variety of unique utilization opportunities. Together with the Orion crew vehicle and ground operations at NASA's Kennedy Space Center in Florida, SLS is a foundational capability for NASA's Journey to Mars. From the beginning of the SLS flight program, utilization of the vehicle will also include launching secondary payloads, including CubeSats, to deep-space destinations. Currently, SLS is making rapid progress toward readiness for its first launch in 2018, using the initial configuration of the vehicle, which is capable of delivering 70 metric tons (t) to Low Earth Orbit (LEO). On its first flight, Exploration Mission-1, SLS will launch an uncrewed test flight of the Orion spacecraft into distant retrograde orbit around the moon. Accompanying Orion on SLS will be 13 CubeSats, which will deploy in cislunar space. These CubeSats will include not only NASA research, but also spacecraft from industry and international partners and potentially academia. Following its first flight and potentially as early as its second, which will launch a crewed Orion spacecraft into cislunar space, SLS will evolve into a more powerful configuration with a larger upper stage. This configuration will initially be able to deliver 105 t to LEO and will continue to be upgraded to a performance of greater than 130 t to LEO. While the addition of the more powerful upper stage will mean a change to the secondary payload accommodations from Block 1, the SLS Program is already evaluating options for future secondary payload opportunities. Early discussions are also already underway for the use of SLS to launch spacecraft on interplanetary trajectories, which could open additional opportunities for CubeSats. This presentation will include an overview of the SLS vehicle and its capabilities, including the current status of progress toward first launch. It will also explain the opportunities the vehicle offers for CubeSats and secondary payloads, including an overview of the CubeSat manifest for Exploration Mission-1 in 2018.

Secondary Payload Opportunities on NASA's Space Launch System (SLS) Enable Science and Deep Space Exploration

NASA Technical Reports Server (NTRS)

Singer, Jody; Pelfrey, Joseph; Norris, George

2016-01-01

For the first time in almost 40 years, a NASA human-rated launch vehicle has completed its Critical Design Review (CDR). With this milestone, NASA's Space Launch System (SLS) and Orion spacecraft are on the path to launch a new era of deep space exploration. This first launch of SLS and the Orion Spacecraft is planned no later than November 2018 and will fly along a trans-lunar trajectory, testing the performance of the SLS and Orion systems for future missions. NASA is making investments to expand the science and exploration capability of the SLS by developing the capability to deploy small satellites during the trans-lunar phase of the mission trajectory. Exploration Mission 1 (EM-1) will include thirteen 6U Cubesat small satellites to be deployed beyond low earth orbit. By providing an earth-escape trajectory, opportunities are created for the advancement of small satellite subsystems, including deep space communications and in-space propulsion. This SLS capability also creates low-cost options for addressing existing Agency strategic knowledge gaps and affordable science missions. A new approach to payload integration and mission assurance is needed to ensure safety of the vehicle, while also maintaining reasonable costs for the small payload developer teams. SLS EM-1 will provide the framework and serve as a test flight, not only for vehicle systems, but also payload accommodations, ground processing, and on-orbit operations. Through developing the requirements and integration processes for EM-1, NASA is outlining the framework for the evolved configuration of secondary payloads on SLS Block upgrades. The lessons learned from the EM-1 mission will be applied to processes and products developed for future block upgrades. In the heavy-lift configuration of SLS, payload accommodations will increase for secondary opportunities including small satellites larger than the traditional Cubesat class payload. The payload mission concept of operations, proposed payload capacity of SLS, and the payload requirements for launch and deployment will be described to provide potential payload users an understanding of this unique exploration capability.

Differential Activity of Striga hermonthica Seed Germination Stimulants and Gigaspora rosea Hyphal Branching Factors in Rice and Their Contribution to Underground Communication

PubMed Central

Cardoso, Catarina; Charnikhova, Tatsiana; Jamil, Muhammad; Delaux, Pierre-Marc; Verstappen, Francel; Amini, Maryam; Lauressergues, Dominique; Ruyter-Spira, Carolien; Bouwmeester, Harro

2014-01-01

Strigolactones (SLs) trigger germination of parasitic plant seeds and hyphal branching of symbiotic arbuscular mycorrhizal (AM) fungi. There is extensive structural variation in SLs and plants usually produce blends of different SLs. The structural variation among natural SLs has been shown to impact their biological activity as hyphal branching and parasitic plant seed germination stimulants. In this study, rice root exudates were fractioned by HPLC. The resulting fractions were analyzed by MRM-LC-MS to investigate the presence of SLs and tested using bioassays to assess their Striga hermonthica seed germination and Gigaspora rosea hyphal branching stimulatory activities. A substantial number of active fractions were revealed often with very different effect on seed germination and hyphal branching. Fractions containing (−)−orobanchol and ent-2'-epi-5-deoxystrigol contributed little to the induction of S. hermonthica seed germination but strongly stimulated AM fungal hyphal branching. Three SLs in one fraction, putative methoxy-5-deoxystrigol isomers, had moderate seed germination and hyphal branching inducing activity. Two fractions contained strong germination stimulants but displayed only modest hyphal branching activity. We provide evidence that these stimulants are likely SLs although no SL-representative masses could be detected using MRM-LC-MS. Our results show that seed germination and hyphal branching are induced to very different extents by the various SLs (or other stimulants) present in rice root exudates. We propose that the development of rice varieties with different SL composition is a promising strategy to reduce parasitic plant infestation while maintaining symbiosis with AM fungi. PMID:25126953

Testing fungistatic properties of soil-like substrate for growing plants in bioregenerative life support systems

NASA Astrophysics Data System (ADS)

Enzhu, Hu; Nesterenko, Elena; Liu, Professor Hong; Manukovsky, N. S.; Kovalev, Vladimir; Gurevich, Yu.; Kozlov, Vladimir; Khizhnyak, Serge; Xing, Yidong; Hu, Enzhu; Enzhu, Hu

There are two ways of getting vegetable food in BLSS: in hydroponic culture and on soil substrates. In any case there is a chance that the plants will be affected by plant pathogenic microorganisms. The subject of the research was a soil-like substrate (SLS) for growing plants in a Bioregenerative Life Support System (BLSS). We estimated the fungistatic properties of SLS using test cultures of Bipolaris and Alternaria plant pathogenic fungi. Experiments were made with the samples of SLS, natural soil and sand (as control). We tested 2 samples of SLS produced by way of bioconversion of wheat and rice straw. We measured the disease severity of wheat seedlings and the incidence of common root rot in natural (non-infectious) background and man-made (infectious) conditions. The severity of disease on the SLS was considerably smaller both in non-infectious and infectious background conditions (8 and 12%) than on the natural soil (18 and 32%) and sand. It was the soil-like substrate that had the minimal value among the variants being compared (20% in non-infectious and 40% in infectious background conditions). This index in respect of the soil was 55 and 78%, correspondingly, and in respect of the sand - 60%, regardless of the background. It was found that SLS significantly suppressed conidia germination of Bipolaris soroikiniana (p<0.001). In the presence of SLS germination of conidia decreased to 9.9 - 12.2% of the control value. No significant differences were found between SLS samples obtained from wheat and rice straw.

Sophorolipid production from lignocellulosic biomass feedstocks

NASA Astrophysics Data System (ADS)

Samad, Abdul

The present study investigated the feasibility of production of sophorolipids (SLs) using yeast Candida bombicola grown on hydrolysates derived lignocellulosic feedstock either with or without supplementing oil as extra carbon source. Several researchers have reported using pure sugars and various oil sources for producing SLs which makes them expensive for scale-up and commercial production. In order to make the production process truly sustainable and renewable, we used feedstocks such as sweet sorghum bagasse, corn fiber and corn stover. Without oil supplementation, the cell densities at the end of day-8 was recorded as 9.2, 9.8 and 10.8 g/L for hydrolysate derived from sorghum bagasse, corn fiber, and corn fiber with the addition of yeast extract (YE) during fermentation, respectively. At the end of fermentation, the SL concentration was 3.6 g/L for bagasse and 1.0 g/L for corn fiber hydrolysate. Among the three major sugars utilized by C. bombicola in the bagasse cultures, glucose was consumed at a rate of 9.1 g/L-day; xylose at 1.8 g/L-day; and arabinose at 0.98 g/L-day. With the addition of soybean oil at 100 g/L, cultures with bagasse hydrolysates, corn fiber hydrolysates and standard medium had a cell content of 7.7 g/L; 7.9 g/L; and 8.9 g/L, respectively after 10 days. The yield of SLs from bagasse hydrolysate was 84.6 g/L and corn fiber hydrolysate was15.6 g/L. In the same order, the residual oil in cultures with these two hydrolysates was 52.3 g/L and 41.0 g/L. For this set of experiment; in the cultures with bagasse hydrolysate; utilization rates for glucose, xylose and arabinose was recorded as 9.5, 1.04 and 0.08 g/L-day respectively. Surprisingly, C. bombicola consumed all monomeric sugars and non-sugar compounds in the hydrolysates and cultures with bagasse hydrolysates had higher yield of SLs than those from a standard medium which contained pure glucose at the same concentration. Based on the SL concentrations and considering all sugars consumed, the yield of SLs was 0.55 g/g carbon (sugars plus oil) for cultures with bagasse hydrolysates. Further, SL production was investigated using sweet sorghum bagasse and corn stover hydrolysates derived from different pretreatment conditions. For the former and latter sugar sources, yellow grease or soybean oil was supplemented at different doses to enhance sophorolipid yield. 14-day batch fermentation on bagasse hydrolysates with 10, 40 and 60 g/L of yellow grease had cell densities of 5.7 g/L, 6.4 g/L and 7.8 g/L, respectively. The study also revealed that the yield of SLs on bagasse hydrolysate decreased from 0.67 to 0.61 and to 0.44 g/g carbon when yellow grease was dosed at 10, 40 and 60 g/L. With aforementioned increasing yellow grease concentration, the residual oil left after 14 days was recorded as 3.2 g/L, 8.5 g/L and 19.9 g/L. For similar experimental conditions, the cell densities observed for corn stover hydrolysate combined with soybean oil at 10, 20 and 40 g/L concentration were 6.1 g/L, 5.9 g/L, and 5.4 g/L respectively. Also, in the same order of oil dose supplemented, the residual oil recovered after 14-day was 8.5 g/L, 8.9 g/L, and 26.9 g/L. Corn stover hydrolysate mixed with the 10, 20 and 40 g/L soybean oil, the SL yield was 0.19, 0.11 and 0.09 g/g carbon. Overall, both hydrolysates supported cell growth and sophorolipid production. The results from this research show that hydrolysates derived from the different lignocellulosic biomass feedstocks can be utilized by C. bombicola to achieve substantial yields of SLs. Based upon the results revealed by several batch-stage experiments, it can be stated that there is great potential for scaling up and industrial scale production of these high value products in future.

The SLS Stages Intertank Structural Test Assembly (STA) arrives at MSFC

NASA Image and Video Library

2018-03-08

The SLS Stages Intertank Structural Test Assembly (STA) is rolling off the NASA Pegasus Barge at the MSFC Dock enroute to the MSFC 4619 Load Test Annex test facility for qualification testing via MSFC West Test Area. STA approaches Test Stand 4693, SLS LH2 test Stand, on way to Bldg. 4619

Preparation of starch-sodium lignosulfonate graft copolymers via laccase catalysis and characterization of antioxidant activity

USDA-ARS?s Scientific Manuscript database

Graft copolymers of waxy maize starch and sodium lignosulfonate (SLS) were prepared by Trametes Versicolor laccase catalysis in aqueous solution. Amount of SLS grafted based on phenol analysis was 0.5% and 1.0% in the absence and presence of 1-hydroxybenzotriazole (HBT), respectively. Starch-SLS gra...

Usefulness of addition of Orvus ES paste and sodium lauryl sulfate to frozen feline semen.

PubMed

Mizutani, Tatsuji; Sumigama, Shiho; Nagakubo, Keiichi; Shimizu, Noriko; Oba, Hiromichi; Hori, Tatsuya; Tsutsui, Toshihiko

2010-01-01

It has been shown that addition of the surfactant Orvus ES paste (OEP) and its main component sodium lauryl sulfate (SLS) to boar or dog semen before freezing improves post-thaw sperm motility and protects acrosome caps. In this study, we investigated the usefulness of the addition of OEP (0, 1, 2 and 4%) or SLS (0, 1, 2, 3 and 4 mg/ml) to cat ejaculates before freezing and their concentrations. Among the OEP addition groups, the 1% OEP group showed higher sperm motility than the other groups. Among the SLS addition groups, the 3 mg/ml SLS group showed slightly higher sperm motility and viability than the other groups. Comparison between the 1% OEP and 3 mg/ml SLS addition groups suggested a higher percentage of sperm with an acrosome cap in the 1% OEP group. The other sperm properties did not significantly differ between the 2 groups. These results indicate that addition of 1% OEP or 3 mg/ml SLS is effective for freezing of cat ejaculated semen.

SLS Model Based Design: A Navigation Perspective

NASA Technical Reports Server (NTRS)

Oliver, T. Emerson; Anzalone, Evan; Park, Thomas; Geohagan, Kevin

2018-01-01

The SLS Program has implemented a Model-based Design (MBD) and Model-based Requirements approach for managing component design information and system requirements. This approach differs from previous large-scale design efforts at Marshall Space Flight Center where design documentation alone conveyed information required for vehicle design and analysis and where extensive requirements sets were used to scope and constrain the design. The SLS Navigation Team is responsible for the Program-controlled Design Math Models (DMMs) which describe and represent the performance of the Inertial Navigation System (INS) and the Rate Gyro Assemblies (RGAs) used by Guidance, Navigation, and Controls (GN&C). The SLS Navigation Team is also responsible for navigation algorithms. The navigation algorithms are delivered for implementation on the flight hardware as a DMM. For the SLS Block 1B design, the additional GPS Receiver hardware model is managed as a DMM at the vehicle design level. This paper describes the models, and discusses the processes and methods used to engineer, design, and coordinate engineering trades and performance assessments using SLS practices as applied to the GN&C system, with a particular focus on the navigation components.

InAs/InGaSb Type-II strained layer superlattice IR detectors

NASA Astrophysics Data System (ADS)

Nathan, Vaidya; Anselm, K. Alex; Lin, C. H. T.; Johnson, Jeffrey L.

2002-05-01

InAs/InGaSb type2 strained layer superlattice (SLS) combines the advantages of III-V materials technology with the strong, broad-band absorption, and wavelength tunability of HgCdTe. In fact, the significantly reduced tunneling and Auger recombination rates in SLS compared to those in HgCdTe should enable SLS detectors to outperform HgCdTe. We report the results of our investigation of InAs/InGaSb type2 strained layer superlattices (SLS)for LWIR photovoltaic detector development. We modeled the band structure, and absorption spectrum of SLS's, and achieved good agreement with experimental data. We systematically investigated the SLS growth conditions, resulting in good uniformity, and the elimination of several defects. We designed, developed and evaluated 16x16 array of 13 micron cutoff photovoltaic detectors. Photodiodes with cutoff wavelengths of 13 and 18microns were demonstrated, which are the longest wavelengths demonstrated for this material system. Quantum efficiencies commensurate with the superlattice thickness were demonstrated and verified at AFRL. The electrical properties show excessive leakage current, most likely due to trap-assisted tunneling.

Enzymatic synthesis of extra virgin olive oil based infant formula fat analogues containing ARA and DHA: one-stage and two-stage syntheses.

PubMed

Pande, Garima; Sabir, Jamal S M; Baeshen, Nabih A; Akoh, Casimir C

2013-11-06

Structured lipids (SLs) with high palmitic acid content at the sn-2 position enriched with arachidonic acid (ARA) and docosahexaenoic acid (DHA) were produced using extra virgin olive oil, tripalmitin, ARA and DHA single cell oil free fatty acids. Four types of SLs were synthesized using immobilized lipases, Novozym 435 and Lipozyme TL IM, based on one-stage (one-pot) and two-stage (sequential) syntheses. The SLs were characterized for fatty acid profile, triacylglycerol (TAG) molecular species, melting and crystallization profiles, tocopherols, and phenolic compounds. All the SLs had >50 mol % palmitic acid at the sn-2 position. The predominant TAGs in all SLs were PPO and OPO. The total tocopherol content of SL1-1, SL1-2, SL2-1, and SL2-2 were 70.46, 68.79, 79.64, and 79.31 μg/g, respectively. SL1-2 had the highest melting completion (42.0 °C) and crystallization onset (27.6 °C) temperatures. All the SLs produced in this study may be suitable as infant formula fat analogues.

In-Flight Suppression of an Unstable F/A-18 Structural Mode Using the Space Launch System Adaptive Augmenting Control System

NASA Technical Reports Server (NTRS)

VanZwieten, Tannen S.; Gilligan, Eric T.; Wall, John H.; Miller, Christopher J.; Hanson, Curtis E.; Orr, Jeb S.

2015-01-01

NASA's Space Launch System (SLS) Flight Control System (FCS) includes an Adaptive Augmenting Control (AAC) component which employs a multiplicative gain update law to enhance the performance and robustness of the baseline control system for extreme off-nominal scenarios. The SLS FCS algorithm including AAC has been flight tested utilizing a specially outfitted F/A-18 fighter jet in which the pitch axis control of the aircraft was performed by a Non-linear Dynamic Inversion (NDI) controller, SLS reference models, and the SLS flight software prototype. This paper describes test cases from the research flight campaign in which the fundamental F/A-18 airframe structural mode was identified using post-flight frequency-domain reconstruction, amplified to result in closed loop instability, and suppressed in-flight by the SLS adaptive control system.

NASA’s Super Guppy Transports SLS Flight Hardware to Kennedy Space Center

NASA Image and Video Library

2018-04-03

NASA's Super Guppy aircraft prepares to depart the U.S. Army’s Redstone Airfield in Huntsville, Alabama, April 3, with flight hardware for NASA’s Space Launch System – the agency’s new, deep-space rocket that will enable astronauts to begin their journey to explore destinations far into the solar system. The Guppy will deliver the Orion stage adapter to NASA’s Kennedy Space Center in Florida for flight preparations. On Exploration Mission-1, the first integrated flight of the SLS and the Orion spacecraft, the adapter will connect Orion to the rocket and carry 13 CubeSats as secondary payloads. SLS will send Orion beyond the Moon, about 280,000 miles from Earth. This is farther from Earth than any spacecraft built for humans has ever traveled. For more information about SLS, visit nasa.gov/sls.

Spinal cord stimulation to abort painful spasms of atypical stiff limb syndrome.

PubMed

Ughratdar, I; Sivakumar, G; Basu, S

2010-01-01

Stiff limb syndrome (SLS) is a rare chronic condition which can result in significant debility. We report the case of a 44-year-old man suffering from severe painful spasms in his right leg with a diagnosis of SLS. He had been initially treated for his pain with a spinal cord stimulator but presented with exacerbation of pain secondary to a lead fracture for which he underwent revision of the stimulator. Postoperative programming unexpectedly resulted in not only control of his pain but also an ability to abort his spasmodic episodes related to SLS. To our knowledge, spinal cord stimulation has not been previously used for SLS and our report opens up another avenue for this rare condition. We provide a brief overview of SLS and propose an underlying mechanism for the observed phenomenon.

Strigolactone-regulated proteins revealed by iTRAQ-based quantitative proteomics in Arabidopsis.

PubMed

Li, Zhou; Czarnecki, Olaf; Chourey, Karuna; Yang, Jun; Tuskan, Gerald A; Hurst, Gregory B; Pan, Chongle; Chen, Jin-Gui

2014-03-07

Strigolactones (SLs) are a new class of plant hormones. In addition to acting as a key inhibitor of shoot branching, SLs stimulate seed germination of root parasitic plants and promote hyphal branching and root colonization of symbiotic arbuscular mycorrhizal fungi. They also regulate many other aspects of plant growth and development. At the transcription level, SL-regulated genes have been reported. However, nothing is known about the proteome regulated by this new class of plant hormones. A quantitative proteomics approach using an isobaric chemical labeling reagent, iTRAQ, to identify the proteome regulated by SLs in Arabidopsis seedlings is presented. It was found that SLs regulate the expression of about three dozen proteins that have not been previously assigned to SL pathways. These findings provide a new tool to investigate the molecular mechanism of action of SLs.

Using Instrumental Variable (IV) Tests to Evaluate Model Specification in Latent Variable Structural Equation Models*

PubMed Central

Kirby, James B.; Bollen, Kenneth A.

2009-01-01

Structural Equation Modeling with latent variables (SEM) is a powerful tool for social and behavioral scientists, combining many of the strengths of psychometrics and econometrics into a single framework. The most common estimator for SEM is the full-information maximum likelihood estimator (ML), but there is continuing interest in limited information estimators because of their distributional robustness and their greater resistance to structural specification errors. However, the literature discussing model fit for limited information estimators for latent variable models is sparse compared to that for full information estimators. We address this shortcoming by providing several specification tests based on the 2SLS estimator for latent variable structural equation models developed by Bollen (1996). We explain how these tests can be used to not only identify a misspecified model, but to help diagnose the source of misspecification within a model. We present and discuss results from a Monte Carlo experiment designed to evaluate the finite sample properties of these tests. Our findings suggest that the 2SLS tests successfully identify most misspecified models, even those with modest misspecification, and that they provide researchers with information that can help diagnose the source of misspecification. PMID:20419054

Methodologies for Verification and Validation of Space Launch System (SLS) Structural Dynamic Models: Appendices

NASA Technical Reports Server (NTRS)

Coppolino, Robert N.

2018-01-01

Verification and validation (V&V) is a highly challenging undertaking for SLS structural dynamics models due to the magnitude and complexity of SLS subassemblies and subassemblies. Responses to challenges associated with V&V of Space Launch System (SLS) structural dynamics models are presented in Volume I of this paper. Four methodologies addressing specific requirements for V&V are discussed. (1) Residual Mode Augmentation (RMA). (2) Modified Guyan Reduction (MGR) and Harmonic Reduction (HR, introduced in 1976). (3) Mode Consolidation (MC). Finally, (4) Experimental Mode Verification (EMV). This document contains the appendices to Volume I.

Effects of ultrasound and sodium lauryl sulfate on the transdermal delivery of hydrophilic permeants: Comparative in vitro studies with full-thickness and split-thickness pig and human skin

PubMed Central

Seto, Jennifer E.; Polat, Baris E.; Lopez, Renata F.V.; Blankschtein, Daniel; Langer, Robert

2010-01-01

The simultaneous application of ultrasound and the surfactant sodium lauryl sulfate (referred to as US/SLS) to skin enhances transdermal drug delivery (TDD) in a synergistic mechanical and chemical manner. Since full-thickness skin (FTS) and split-thickness skin (STS) differ in mechanical strength, US/SLS treatment may have different effects on their transdermal transport pathways. Therefore, we evaluated STS as an alternative to the well-established US/SLS-treated FTS model for TDD studies of hydrophilic permeants. We utilized the aqueous porous pathway model to compare the effects of US/SLS treatment on the skin permeability and the pore radius of pig and human FTS and STS over a range of skin electrical resistivity values. Our findings indicate that the US/SLS-treated pig skin models exhibit similar permeabilities and pore radii, but the human skin models do not. Furthermore, the US/SLS-enhanced delivery of gold nanoparticles and quantum dots (two model hydrophilic macromolecules) is greater through pig STS than through pig FTS, due to the presence of less dermis that acts as an artificial barrier to macromolecules. In spite of greater variability in correlations between STS permeability and resistivity, our findings strongly suggest the use of 700-μm-thick pig STS to investigate the in vitro US/SLS-enhanced delivery of hydrophilic macromolecules. PMID:20346994

Use of DES Modeling for Determining Launch Availability for SLS

NASA Technical Reports Server (NTRS)

Watson, Mike; Staton, Eric; Cates, Grant; Finn, Ron; Altino, Karen; Burns, Lee

2014-01-01

The National Aeronautics and Space Administration (NASA) is developing new capabilities for human and scientific exploration beyond Earth's orbit. This effort includes the Space Shuttle derived Space Launch System (SLS), the Multi-Purpose Crew Vehicle (MPCV) "Orion", and the Ground Systems Development and Operations (GSDO). There are several requirements and Technical Performance Measures (TPMs) that have been levied by the Exploration Systems Development (ESD) upon the SLS, MPCV, and GSDO Programs including an integrated Launch Availability (LA) TPM. The LA TPM is used to drive into the SLS, Orion and GSDO designs a high confidence of successfully launching exploration missions that have narrow Earth departure windows. The LA TPM takes into consideration the reliability of the overall system (SLS, Orion and GSDO), natural environments, likelihood of a failure, and the time required to recover from an anomaly. A challenge with the LA TPM is the interrelationships between SLS, Orion, GSDO and the natural environments during launch countdown and launch delays that makes it impossible to develop an analytical solution for calculating the integrated launch probability. This paper provides an overview of how Discrete Event Simulation (DES) modeling was used to develop the LA TPM, how it was allocated down to the individual programs, and how the LA analysis is being used to inform and drive the SLS, Orion, and GSDO designs to ensure adequate launch availability for future human exploration.

Genetic homogeneity in Sjoegren-Larsson syndrome: Linkage to chromosome 17p in families of different non-Swedish ethnic origins

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rogers, G.R.; Lee, M.; Compton, J.G.

1995-11-01

Sjoegren-Larsson syndrome (SLS) is a rare, autosomal recessive disorder that is characterized by congenital ichthyosis, mental retardation, and spastic diplegia or tetraplegia. Three United States families, three Egyptian families, and one Israeli Arab family were investigated for linkage of the SLS gene to a region of chromosome 17. Pairwise and multipoint linkage analysis with nine markers mapped the SLS gene to the same region of the genome as that reported in Swedish SLS pedigrees. Examination of recombinants by haplotype analysis showed that the gene lies in the region containing the markers D17S953, D17S805, D17S689, and D17S842. D17S805 is pericentromeric onmore » 17p. Patients in two consanguineous Egyptian families were homozygous at the nine marker loci tested, and another patient from a third family was homozygous for eight of the nine, suggesting that within each of these families the region of chromosome 17 carrying the SLS gene is identical by descent. Linkage of the SLS gene to chromosome 17p in families of Arabic, mixed European, Native American, and Swedish descent provides evidence for a single SLS locus and should prove useful for diagnosis and carrier detection in worldwide cases. 25 refs., 4 figs., 1 tab.« less

Use of DES Modeling for Determining Launch Availability for SLS

NASA Technical Reports Server (NTRS)

Staton, Eric; Cates, Grant; Finn, Ronald; Altino, Karen M.; Burns, K. Lee; Watson, Michael D.

2014-01-01

The National Aeronautics and Space Administration (NASA) is developing new capabilities for human and scientific exploration beyond Earth's orbit. This effort includes the Space Shuttle derived Space Launch System (SLS), the Orion Multi-Purpose Crew Vehicle (MPCV), and the Ground Systems Development and Operations (GSDO). There are several requirements and Technical Performance Measures (TPMs) that have been levied by the Exploration Systems Development (ESD) upon the SLS, Orion, and GSDO Programs including an integrated Launch Availability (LA) TPM. The LA TPM is used to drive into the SLS, Orion and GSDO designs a high confidence of successfully launching exploration missions that have narrow Earth departure windows. The LA TPM takes into consideration the reliability of the overall system (SLS, Orion and GSDO), natural environments, likelihood of a failure, and the time required to recover from an anomaly. A challenge with the LA TPM is the interrelationships between SLS, Orion, GSDO and the natural environments during launch countdown and launch delays that makes it impossible to develop an analytical solution for calculating the integrated launch probability. This paper provides an overview of how Discrete Event Simulation (DES) modeling was used to develop the LA TPM, how it was allocated down to the individual programs, and how the LA analysis is being used to inform and drive the SLS, Orion, and GSDO designs to ensure adequate launch availability for future human exploration.

Materials Research Society Symposium Proceedings, Volume 758 Held in Boston, Massachusetts on December 3-5, 2002. Rapid Prototyping Technologies

DTIC Science & Technology

2003-04-01

lithography to associate curved and conical structures with the smooth and vertical walls and micrometer accuracy of SU-8 technology [24]. It has been...Sintering (SLS) -3D O Stereolithography (SLA) - 3D Systems Systems Curing with Visible Light and DMD Melting with Lasers 0 Direct Photo Shaping (DPS...LAM) - AeroMet Electrolyte 0 Direct Metal Dep. ( DMD ) - POM Electroplating * Electrochemical Fab. (EFAB) - USC BINDER-based Drop Binding Powder Printing

Space Launch System Booster Test- Behind the Scenes

NASA Image and Video Library

2016-06-24

Get a sneak peek behind the scenes of how engineers and technicians at Orbital ATK in Promontory, Utah, are coming together to test the most powerful booster for NASA’s new rocket, the Space Launch System. SLS will make missions possible to an asteroid and the journey to Mars. For more information on SLS, visit www.nasa.gov/sls.

An Alternative Two Stage Least Squares (2SLS) Estimator for Latent Variable Equations.

ERIC Educational Resources Information Center

Bollen, Kenneth A.

1996-01-01

An alternative two-stage least squares (2SLS) estimator of the parameters in LISREL type models is proposed and contrasted with existing estimators. The new 2SLS estimator allows observed and latent variables to originate from nonnormal distributions, is consistent, has a known asymptotic covariance matrix, and can be estimated with standard…

Greenhouse gas and ammonia emissions from digested and separated dairy manure during storage and after land application

USDA-ARS?s Scientific Manuscript database

Manure management at dairy production facilities, including anaerobic digestion (AD) and solid-liquid separation (SLS), has a strong potential for the abatement of greenhouse gas (GHG) and ammonia (NH3) emissions. This study evaluated the effects of AD, SLS, and AD+SLS on GHG and NH3 emissions durin...

Assessment and Verification of SLS Block 1-B Exploration Upper Stage State and Stage Disposal Performance

NASA Technical Reports Server (NTRS)

Patrick, Sean; Oliver, Emerson

2018-01-01

One of the SLS Navigation System's key performance requirements is a constraint on the payload system's delta-v allocation to correct for insertion errors due to vehicle state uncertainty at payload separation. The SLS navigation team has developed a Delta-Delta-V analysis approach to assess the effect on trajectory correction maneuver (TCM) design needed to correct for navigation errors. This approach differs from traditional covariance analysis based methods and makes no assumptions with regard to the propagation of the state dynamics. This allows for consideration of non-linearity in the propagation of state uncertainties. The Delta-Delta-V analysis approach re-optimizes perturbed SLS mission trajectories by varying key mission states in accordance with an assumed state error. The state error is developed from detailed vehicle 6-DOF Monte Carlo analysis or generated using covariance analysis. These perturbed trajectories are compared to a nominal trajectory to determine necessary TCM design. To implement this analysis approach, a tool set was developed which combines the functionality of a 3-DOF trajectory optimization tool, Copernicus, and a detailed 6-DOF vehicle simulation tool, Marshall Aerospace Vehicle Representation in C (MAVERIC). In addition to delta-v allocation constraints on SLS navigation performance, SLS mission requirement dictate successful upper stage disposal. Due to engine and propellant constraints, the SLS Exploration Upper Stage (EUS) must dispose into heliocentric space by means of a lunar fly-by maneuver. As with payload delta-v allocation, upper stage disposal maneuvers must place the EUS on a trajectory that maximizes the probability of achieving a heliocentric orbit post Lunar fly-by considering all sources of vehicle state uncertainty prior to the maneuver. To ensure disposal, the SLS navigation team has developed an analysis approach to derive optimal disposal guidance targets. This approach maximizes the state error covariance prior to the maneuver to develop and re-optimize a nominal disposal maneuver (DM) target that, if achieved, would maximize the potential for successful upper stage disposal. For EUS disposal analysis, a set of two tools was developed. The first considers only the nominal pre-disposal maneuver state, vehicle constraints, and an a priori estimate of the state error covariance. In the analysis, the optimal nominal disposal target is determined. This is performed by re-formulating the trajectory optimization to consider constraints on the eigenvectors of the error ellipse applied to the nominal trajectory. A bisection search methodology is implemented in the tool to refine these dispersions resulting in the maximum dispersion feasible for successful disposal via lunar fly-by. Success is defined based on the probability that the vehicle will not impact the lunar surface and will achieve a characteristic energy (C3) relative to the Earth such that it is no longer in the Earth-Moon system. The second tool propagates post-disposal maneuver states to determine the success of disposal for provided trajectory achieved states. This is performed using the optimized nominal target within the 6-DOF vehicle simulation. This paper will discuss the application of the Delta-Delta-V analysis approach for performance evaluation as well as trajectory re-optimization so as to demonstrate the system's capability in meeting performance constraints. Additionally, further discussion of the implementation of assessing disposal analysis will be provided.

Whole Gene Capture Analysis of 15 CRC Susceptibility Genes in Suspected Lynch Syndrome Patients.

PubMed

Jansen, Anne M L; Geilenkirchen, Marije A; van Wezel, Tom; Jagmohan-Changur, Shantie C; Ruano, Dina; van der Klift, Heleen M; van den Akker, Brendy E W M; Laros, Jeroen F J; van Galen, Michiel; Wagner, Anja; Letteboer, Tom G W; Gómez-García, Encarna B; Tops, Carli M J; Vasen, Hans F; Devilee, Peter; Hes, Frederik J; Morreau, Hans; Wijnen, Juul T

2016-01-01

Lynch Syndrome (LS) is caused by pathogenic germline variants in one of the mismatch repair (MMR) genes. However, up to 60% of MMR-deficient colorectal cancer cases are categorized as suspected Lynch Syndrome (sLS) because no pathogenic MMR germline variant can be identified, which leads to difficulties in clinical management. We therefore analyzed the genomic regions of 15 CRC susceptibility genes in leukocyte DNA of 34 unrelated sLS patients and 11 patients with MLH1 hypermethylated tumors with a clear family history. Using targeted next-generation sequencing, we analyzed the entire non-repetitive genomic sequence, including intronic and regulatory sequences, of 15 CRC susceptibility genes. In addition, tumor DNA from 28 sLS patients was analyzed for somatic MMR variants. Of 1979 germline variants found in the leukocyte DNA of 34 sLS patients, one was a pathogenic variant (MLH1 c.1667+1delG). Leukocyte DNA of 11 patients with MLH1 hypermethylated tumors was negative for pathogenic germline variants in the tested CRC susceptibility genes and for germline MLH1 hypermethylation. Somatic DNA analysis of 28 sLS tumors identified eight (29%) cases with two pathogenic somatic variants, one with a VUS predicted to pathogenic and LOH, and nine cases (32%) with one pathogenic somatic variant (n = 8) or one VUS predicted to be pathogenic (n = 1). This is the first study in sLS patients to include the entire genomic sequence of CRC susceptibility genes. An underlying somatic or germline MMR gene defect was identified in ten of 34 sLS patients (29%). In the remaining sLS patients, the underlying genetic defect explaining the MMRdeficiency in their tumors might be found outside the genomic regions harboring the MMR and other known CRC susceptibility genes.

Effects of extract liquid of SLS made from three different materials on seed germination and seedling growth of rice

NASA Astrophysics Data System (ADS)

Shao, Lingzhi; Fu, Wenting; Liu, Hong; Yan, Min; Li, Leyuan

Rice and wheat are the main candidate crops in the bioregenerative life support system (BLSS) of China, for they are traditional food in Asia. Thus the recycling of their straws is an important issue in our BLSS, and it is a vital way to biologically process them into the soil like substrate (SLS) first and then reuse them in the plant cultivation system to achieve their recycle in BLSS. However, rice is a plant with strong allelopathic effects. And so far, it is also not clear that what kind of raw materials can be processed into proper SLS to grow rice in the BLSS. Therefore, in this study, the extract liquid of SLS made from three different materials including rice straw, wheat straw and rice-wheat mixed straw was utilized to investigate its effects on the seed germination and seedling growth of rice. The gradients of the extract concentrations (soil: water) were 1:3, 1:5, 1:9, and 1:15 with the deionized water used as control. The effects of different types of SLS on seed germination and seedling vitality of rice were confirmed by analyzing the germination rate, seedling length, root length, root fresh weight, seedling fresh weight and other indicates. In addition, based on the analysis towards pH, organic matter composition and other factors of the SLS as well as the chlorophyll and hormone content of rice, the mechanism of the inhibition was speculated and the preventive methods of this phenomenon was explored. Finally, the feasibility of cultivating rice on the SLS made from the above three kinds of raw materials was evaluated and the proper raw materials to be processed into SLS to grow rice were determined.

In-Flight Suppression of a Destabilized F/A-18 Structural Mode Using the Space Launch System Adaptive Augmenting Control System

NASA Technical Reports Server (NTRS)

Wall, John H.; VanZwieten, Tannen S.; Gilligan, Eric T.; Miller, Christopher J.; Hanson, Curtis E.; Orr, Jeb S.

2015-01-01

NASA's Space Launch System (SLS) Flight Control System (FCS) includes an Adaptive Augmenting Control (AAC) component which employs a multiplicative gain update law to enhance the performance and robustness of the baseline control system for extreme off nominal scenarios. The SLS FCS algorithm including AAC has been flight tested utilizing a specially outfitted F/A-18 fighter jet in which the pitch axis control of the aircraft was performed by a Non-linear Dynamic Inversion (NDI) controller, SLS reference models, and the SLS flight software prototype. This paper describes test cases from the research flight campaign in which the fundamental F/A-18 airframe structural mode was identified using frequency-domain reconstruction of flight data, amplified to result in closed loop instability, and suppressed in-flight by the SLS adaptive control system.

Sunflower seeds as eliciting agents of Compositae dermatitis.

PubMed

Paulsen, Evy; El-Houri, Rime B; Andersen, Klaus E; Christensen, Lars P

2015-03-01

Sunflowers may cause dermatitis because of allergenic sesquiterpene lactones (SLs). Contact sensitization to sunflower seeds has also been reported, but the allergens are unknown. To analyse sunflower seeds for the presence of SLs and to assess the prevalence of sunflower sensitization in Compositae-allergic individuals. Sunflower-sensitive patients were identified by aimed patch testing. A dichloromethane extract of whole sunflower seeds was analysed by liquid chromatography-mass spectrometry and high-performance liquid chromatography. The prevalence of sensitivity to sunflower in Compositae-allergic individuals was 56%. A solvent wash of whole sunflower seeds yielded an extract containing SLs, the principal component tentatively being identified as argophyllin A or B, other SLs being present in minute amounts. The concentration of SLs on the sunflower seeds is considered high enough to elicit dermatitis in sensitive persons, and it seems appropriate to warn Compositae-allergic subjects against handling sunflower seeds. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

NASA's Space Launch System (SLS): A New National Capability

NASA Technical Reports Server (NTRS)

May, Todd A.

2012-01-01

The National Aeronautics and Space Administration's (NASA's) Space Launch System (SLS) will contribute a new national capability for human space flight and scientific missions to low- Earth orbit (LEO) and beyond. Exploration beyond Earth orbit will be an enduring legacy to future generations, confirming America s desire to explore, learn, and progress. The SLS Program, managed at NASA s Marshall Space Fight Center, will develop the heavy lift vehicle that will launch the Orion Multi-Purpose Crew Vehicle (MPCV), equipment, supplies, and science experiments for missions beyond Earth s orbit. This paper gives an overview of the SLS design and management approach against a backdrop of the missions it will empower. It will detail the plan to move from the computerized drawing board to the launch pad in the near term, as well as summarize the innovative approaches the SLS team is applying to deliver a safe, affordable, and sustainable long-range national capability.

The SLS Stages Intertank Structural Test Assembly (STA) arrives at MSFC

NASA Image and Video Library

2018-03-08

The SLS Stages Intertank Structural Test Assembly (STA) is rolling off the NASA Pegasus Barge at the MSFC Dock enroute to the MSFC 4619 Load Test Annex test facility for qualification testing via MSFC West Test Area. Historic Saturn 1-C test stand on far left, blockhouse 4670 on far right, SLS LH2 test stand, 4693, in center.

Effects of addition of sodium lauryl sulfate on frozen-thawed canine spermatozoa.

PubMed

Hori, Tatsuya; Kaseki, Hanae; Fukuhara, Youko; Oba, Hiromichi; Mizutani, Tatsuji; Kawakami, Eiichi; Tsutsui, Toshihiko

2006-10-01

The addition of Orvus ES paste (OEP) to extender may be essential for preparing frozen dog semen. The major ingredient of OEP is sodium lauryl sulfate (SLS). In this study, we compared the effect of SLS on frozen dog semen with that of OEP. There were no significant differences between the 2-mg/ml SLS group and OEP group concerning sperm motility, viability and the percentage of viable sperm with intact acrosomes after freeze-thawing. These results suggest that the effectiveness of frozen dog semen extender containing 2 mg/ml of SLS is similar effective to that demonstrated for OEP.

Video Intertank for the Core Stage for the first SLS Flight

NASA Image and Video Library

2017-06-29

This video shows the Space Launch System interank, which recently completed assembly at NASA's Michoud Assembly Facility in New Orleans. This tank was bolted together with more than 7,000 bolts. It is the only part of the SLS core stage assembly with bolts rather than by welding. The rocket's interank is located between the core stage liquid oxygen and liquid hydrogen fuel tanks. It has to be strong because the two SLS solid rocket boosters attache to the sides of it. This flight article will be connected to four other parts to form the core stage for the first integrated flight of SLS and Orion.

Induction of a Hardening Phenomenon and Quantitative Changes of Ceramides in Stratum Corneum

PubMed Central

Park, Sook Young; Kim, Jin Hye; Cho, Soo Ick; Kim, Kyeong Il; Cho, Hee Jin; Park, Chun Wook; Lee, Cheol Heon

2014-01-01

Background Hardening phenomenon of human skin after repeated exposure to the irritants is well-known, but the precise mechanism remains elusive. Objective To modify the previous experimental model of hardening phenomenon by repeated applications of two different concentrations of sodium lauryl sulfate (SLS) solutions to Korean healthy volunteers and to investigate the quantitative changes of ceramides in stratum corneum before and after chronic repeated irritation. Methods Eight hundred microliters of distilled water containing 0.1% and 2% SLS was applied for 10 minutes on the forearm of 41 healthy volunteers for 3 weeks. After an intervening 3-week rest, 24-hour patch tests with 1% SLS were conducted on previously irritated sites. Transepidermal water loss (TEWL), erythema index and quantity of ceramide were measured in the stratum corneum before and after irritation. Results TEWL values on the sites preirritated with 2% SLS were lower than those with 0.1% SLS. Hardening phenomenon occurred in 24 volunteers at day 44. The changes in ceramide levels were not significantly higher in the hardened skin than in the non-hardened skin. Conclusion Repetitive stimulation with a higher concentration of SLS can more easily trigger skin hardening. PMID:24648684

Sodium lauryl sulfate impedes drug release from zinc-crosslinked alginate beads: switching from enteric coating release into biphasic profiles.

PubMed

Taha, Mutasem O; Nasser, Wissam; Ardakani, Adel; Alkhatib, Hatim S

2008-02-28

The aim of this research is to investigate the effects of sodium lauryl sulfate (SLS) on ionotropically cross-linked alginate beads. Different levels of SLS were mixed with sodium alginate and chlorpheniramine maleate (as loaded model drug). The resulting viscous solutions were dropped onto aqueous solutions of zinc or calcium ions for ionotropic curing. The generated beads were assessed by their drug releasing profiles, infrared and differential scanning colorimetery (DSC) traits. SLS was found to exert profound concentration-dependent impacts on the characteristics of zinc-crosslinked alginate beads such that moderate modifications in the levels of SLS switched drug release from enteric coating-like behavior to a biphasic release modifiable to sustained-release by the addition of minute amounts of xanthan gum. Calcium cross-linking failed to reproduce the same behavior, probably due to the mainly ionic nature of calcium-carboxylate bonds compared to the coordinate character of their zinc-carboxylate counterparts. Apparently, moderate levels of SLS repel water penetration into the beads, and therefore minimize chlorpheniramine release. However, higher SLS levels seem to discourage polymeric cross-linking and therefore allow biphasic drug release.

Solid-state fermentation of rice straw residues for its use as growing medium in ornamental nurseries

NASA Astrophysics Data System (ADS)

Belal, Elsayed B.; El-Mahrouk, M. E.

2010-11-01

This work was conducted at a private nursery in Kafr El-Sheikh governorate to investigate the bioconversion of rice straw into a soil-like substrate (SLS) by Phanerochaete chrysosporium and Trichoderma hazianum and the possibility of using rice straw compost in ornamental nurseries as a partial or total replacement of coconut peat (CP) and vermiculite (V) in the growing medium. The results showed that rice straw could be treated better by aerobic fermentation. The authors used five mixtures as follows: (1) Control (CP+V at 1:1 v/v), (2) SLS (100%), (3) SLS+CP (1:1 v/v), (4) SLS+V (1:1 v/v), and (5) SLS+CP+V (1:1:1 v/v/v). Data were recorded as seedling height, no. of leaves, shoot fresh and dry weights, root length and root fresh and dry weights in order to assess the quality of both transplants of Althea rosea (hollyhock) and Calendula officinalis (scotch marigold). Hollyhock seedlings grown in medium containing a mixture of SLS+CP+V displayed quality traits similar to those recorded from the control treatment, while scotch marigold seedlings in the same medium followed the control medium in quality.

Survival of human-associated bacteria in SLS

NASA Astrophysics Data System (ADS)

Fu, Yuming; Tikhomirov, Alexander A.; Nickolay Manukovsky, D..; Khizhnyak, Sergey; Kovalev, Vladimir

2016-07-01

Management of microbial communities to minimize the potential for risk to the crew and to the plants to be used for supporting the crew is an essential component of successful bioregenerative life support systems (BLSS). Previously it was shown that soil-like substrate (SLS), obtained as a result of bioconversion of non-edible plant biomass in the higher plants based BLSS, demonstrates strong anti-fungal activity against soil-borne plant pathogens (Nesterenko et al., 2009). The present study is devoted to the estimation of anti-bacterial activity of SLS against gram-negative (presented with Escherichia coli) and gram-positive (presented with Staphylococcus aureus) human-associated bacteria, both of which belong to the group of opportunistic pathogen. In vitro effects of different types of SLS on E. coli and S. aureus and in situ survival curves of the bacteria with corresponding math models are presented. Additionally we have examined the influence of community richness (the indigenous community of SLS) on the ability of introduced human-associated bacteria to persist within SLS. The work was carried out within the frames of the state task on the subject No 56.1.4 of the Basic Research Program (Section VI) of Russian State Academies for 2013-2020.

Corneal protection with high-molecular-weight hyaluronan against in vitro and in vivo sodium lauryl sulfate-induced toxic effects.

PubMed

Pauloin, Thierry; Dutot, Mélody; Liang, Hong; Chavinier, Emilie; Warnet, Jean-Michel; Rat, Patrice

2009-10-01

The aim of this study was to investigate high-molecular-weight hyaluronan (HA-HMW) corneal protection against sodium lauryl sulfate (SLS)-induced toxic effects with in vitro and in vivo experimental approaches. In vitro experiments consisted of a human corneal epithelial cell line incubated with HA-HMW, rinsed, and incubated with SLS. Cell viability, oxidative stress, chromatin condensation, caspase-3, -8, -9, and P2X7 cell death receptor activation, interleukin-6, and interleukin-8 production were investigated. In vivo experiments consisted of 36 New Zealand white rabbits treated for 3 days, 3 times per day, with HA-HMW or phosphate-buffered salt solution. At day 4, eyes were treated with SLS. Clinical observation and in vivo confocal microscopy using the Rostock Cornea Module of the Heidelberg Retina Tomograph-II were performed to evaluate and to compare SLS-induced toxicity between eyes treated with HA-HMW and eyes treated with phosphate-buffered salt solution. In vitro data indicate that exposure of human corneal epithelial cells to HA-HMW significantly decreased SLS-induced oxidative stress, apoptosis, and inflammation cytokine production. In vivo data indicate that SLS cornea injuries, characterized by damaged corneal epithelium, damaged anterior stroma, and inflammatory infiltrations, were attenuated with HA-HMW treatment. A good correlation was seen between in vitro and in vivo findings showing that HA-HMW decreases SLS-induced toxic effects and protects cornea.

Effects of ultrasound and sodium lauryl sulfate on the transdermal delivery of hydrophilic permeants: Comparative in vitro studies with full-thickness and split-thickness pig and human skin.

PubMed

Seto, Jennifer E; Polat, Baris E; Lopez, Renata F V; Blankschtein, Daniel; Langer, Robert

2010-07-01

The simultaneous application of ultrasound and the surfactant sodium lauryl sulfate (referred to as US/SLS) to skin enhances transdermal drug delivery (TDD) in a synergistic mechanical and chemical manner. Since full-thickness skin (FTS) and split-thickness skin (STS) differ in mechanical strength, US/SLS treatment may have different effects on their transdermal transport pathways. Therefore, we evaluated STS as an alternative to the well-established US/SLS-treated FTS model for TDD studies of hydrophilic permeants. We utilized the aqueous porous pathway model to compare the effects of US/SLS treatment on the skin permeability and the pore radius of pig and human FTS and STS over a range of skin electrical resistivity values. Our findings indicate that the US/SLS-treated pig skin models exhibit similar permeabilities and pore radii, but the human skin models do not. Furthermore, the US/SLS-enhanced delivery of gold nanoparticles and quantum dots (two model hydrophilic macromolecules) is greater through pig STS than through pig FTS, due to the presence of less dermis that acts as an artificial barrier to macromolecules. In spite of greater variability in correlations between STS permeability and resistivity, our findings strongly suggest the use of 700microm-thick pig STS to investigate the in vitro US/SLS-enhanced delivery of hydrophilic macromolecules. 2010 Elsevier B.V. All rights reserved.

Sls1p is a membrane-bound regulator of transcription-coupled processes involved in Saccharomyces cerevisiae mitochondrial gene expression.

PubMed Central

Bryan, Anthony C; Rodeheffer, Matthew S; Wearn, Christopher M; Shadel, Gerald S

2002-01-01

Mitochondrial translation is largely membrane-associated in S. cerevisiae. Recently, we discovered that the matrix protein Nam1p binds the amino-terminal domain of yeast mtRNA polymerase to couple translation and/or RNA-processing events to transcription. To gain additional insight into these transcription-coupled processes, we performed a genetic screen for genes that suppress the petite phenotype of a point mutation in mtRNA polymerase (rpo41-R129D) when overexpressed. One suppressor identified in this screen was SLS1, which encodes a mitochondrial membrane protein required for assembly of respiratory-chain enzyme complexes III and IV. The mtRNA-processing defects associated with the rpo41-R129D mutation were corrected in the suppressed strain, linking Sls1p to a pathway that includes mtRNA polymerase and Nam1p. This was supported by the observation that SLS1 overexpression rescued the petite phenotype of a NAM1 null mutation. In contrast, overexpression of Nam1p did not rescue the petite phenotype of a SLS1 null mutation, indicating that Nam1p and Sls1p are not functionally redundant but rather exist in an ordered pathway. On the basis of these data, a model in which Nam1p coordinates the delivery of newly synthesized transcripts to the membrane, where Sls1p directs or regulates their subsequent handling by membrane-bound factors involved in translation, is proposed. PMID:11805046

Novel Twin Streptolysin S-Like Peptides Encoded in the sag Operon Homologue of Beta-Hemolytic Streptococcus anginosus

PubMed Central

Tabata, Atsushi; Nakano, Kota; Ohkura, Kazuto; Tomoyasu, Toshifumi; Kikuchi, Ken; Whiley, Robert A.

2013-01-01

Streptococcus anginosus is a member of the anginosus group streptococci, which form part of the normal human oral flora. In contrast to the pyogenic group streptococci, our knowledge of the virulence factors of the anginosus group streptococci, including S. anginosus, is not sufficient to allow a clear understanding of the basis of their pathogenicity. Generally, hemolysins are thought to be important virulence factors in streptococcal infections. In the present study, a sag operon homologue was shown to be responsible for beta-hemolysis in S. anginosus strains by random gene knockout. Interestingly, contrary to pyogenic group streptococci, beta-hemolytic S. anginosus was shown to have two tandem sagA homologues, encoding streptolysin S (SLS)-like peptides, in the sag operon homologue. Gene deletion and complementation experiments revealed that both genes were functional, and these SLS-like peptides were essential for beta-hemolysis in beta-hemolytic S. anginosus. Furthermore, the amino acid sequence of these SLS-like peptides differed from that of the typical SLS of S. pyogenes, especially in their propeptide domain, and an amino acid residue indicated to be important for the cytolytic activity of SLS in S. pyogenes was deleted in both S. anginosus homologues. These data suggest that SLS-like peptides encoded by two sagA homologues in beta-hemolytic S. anginosus may be potential virulence factors with a different structure essential for hemolytic activity and/or the maturation process compared to the typical SLS present in pyogenic group streptococci. PMID:23292771

Expression and evolution of delta9 and delta11 desaturase genes in the moth Spodoptera littoralis.

PubMed

Rodríguez, Sergio; Hao, Guixia; Liu, Weitian; Piña, Benjamín; Rooney, Alejandro P; Camps, Francisco; Roelofs, Wendell L; Fabriàs, Gemma

2004-12-01

Desaturation of fatty acids is a key reaction in the biosynthesis of moth sex pheromones. The main component of Spodoptera littoralis sex pheromone blend is produced by the action of Delta11 and Delta9 desaturases. In this article, we report on the cloning of four desaturase-like genes in this species: one from the fat body (Sls-FL1) and three (Sls-FL2, Sls-FL3 and Sls-FL4) from the pheromone gland. By means of a computational/phylogenetic method, as well as functional assays, the desaturase gene products have been characterized. The fat body gene expressed a Delta9 desaturase that produced (Z)-9-hexadecenoic and (Z)-9-octadecenoic acids in a (1:4.5) ratio, whereas the pheromone gland Sls-FL2 expressed a Delta9 desaturase that produced (Z)-9-hexadecenoic and (Z)-9-octadecenoic acids in a (1.5:1) ratio. Although both Delta9 desaturases produced (Z)-9-tetradecenoic acid from myristic acid, transformed yeast grown in the presence of a mixture of myristic and (E)-11-tetradecenoic acids produced (Z,E)-9,11-tetradecadienoic acid, but not (Z)-9-tetradecenoic acid. The Sls-FL3 gene expressed a protein that produced a mixture of (E)-11-tetradecenoic, (Z)-11-tetradecenoic, (Z)-11-hexadecenoic and (Z)-11-octadecenoic acids in a 5:4:60:31 ratio. Despite having all the characteristics of a desaturase gene, no function could be found for Sls-FL4.

NASA's Space Launch System Program Update

NASA Technical Reports Server (NTRS)

May, Todd; Lyles, Garry

2015-01-01

Hardware and software for the world's most powerful launch vehicle for exploration is being welded, assembled, and tested today in high bays, clean rooms and test stands across the United States. NASA's Space Launch System (SLS) continued to make significant progress in 2014 with more planned for 2015, including firing tests of both main propulsion elements and the program Critical Design Review (CDR). Developed with the goals of safety, affordability, and sustainability, SLS will still deliver unmatched capability for human and robotic exploration. The initial Block 1 configuration will deliver more than 70 metric tons of payload to low Earth orbit (LEO). The evolved Block 2 design will deliver some 130 metric tons to LEO. Both designs offer enormous opportunity and flexibility for larger payloads, simplifying payload design as well as ground and on-orbit operations, shortening interplanetary transit times, and decreasing overall mission risk. Over the past year, every vehicle element has manufactured or tested hardware. An RS-25 liquid propellant engine was hotfire-tested at NASA's Stennis Space Center, Miss. for the first time since 2009 exercising and validating the new engine controller, the renovated A-1 test stand, and the test teams. Four RS-25s will power the SLS core stage. A qualification five-segment solid rocket motor incorporating several design, material, and process changes was scheduled to be test-fired in March at the prime contractor's facility in Utah. The booster also successfully completed its Critical Design Review (CDR) validating the planned design. All six major manufacturing tools for the core stage are in place at the Michoud Assembly Facility in Louisiana, and have been used to build numerous pieces of confidence, qualification, and even flight hardware, including barrel sections, domes and rings used to assemble the world's largest rocket stage. SLS Systems Engineering accomplished several key tasks including vehicle avionics software and hardware build and testing, scale model acoustic and base heating tests. Construction of the Interim Cryogenic Propulsion Stage (ICPS) began. Advanced development provided a look into the future of SLS. Shell buckling knockdown factor testing refined decades-old design margins that added thousands of pounds to rocket payloads. Adaptive manufacturing and structured light scanning development promised to cut the cost and time associated with manufacturing and testing. This paper will provide an overview of the progress made over the past year and provide a glimpse of 2015 milestones and beyond on the way to the first launch in 2018.

STS-40 MS Jernigan, working at SLS-1 Rack 1, examines Pilot Gutierrez's ear

NASA Image and Video Library

1991-06-14

STS040-206-002 (5-14 June 1991) --- Held in place by the Spacelab Life Sciences (SLS-1) Medical Restraint System (MRS), astronaut Sidney M. Gutierrez, pilot, gets his ears checked by astronaut Tamara E. Jernigan, mission specialist. The two are in the SLS-1 module, onboard the Space Shuttle Columbia. The scene was photographed with a 35mm camera.

NASA's Space Launch System: Momentum Builds Toward First Launch

NASA Technical Reports Server (NTRS)

May, Todd A.; Lyles, Garry M.

2014-01-01

NASA's Space Launch System (SLS) is gaining momentum toward the first launch of a new exploration-class heavy lift launch vehicle for international exploration and science initiatives. The SLS comprises an architecture that begins with a vehicle capable of launching 70 metric tons (t) into low Earth orbit. It will launch the Orion Multi-Purpose Crew Vehicle (MPCV) on its first autonomous flight beyond the Moon and back in December 2017. Its first crewed flight follows in 2021. SLS can evolve to a130-t lift capability and serve as a baseline for numerous robotic and human missions ranging from a Mars sample return to delivering the first astronauts to explore another planet. The SLS Program formally transitioned from the formulation phase to implementation with the successful completion of the rigorous Key Decision Point C review in 2014. As a result, the Agency authorized the Program to move forward to Critical Design Review, scheduled for 2015. In the NASA project life cycle process, SLS has completed 50 percent of its major milestones toward first flight. Every SLS element manufactured development hardware for testing over the past year. Accomplishments during 2013/2014 included manufacture of core stage test articles, preparations for qualification testing the solid rocket boosters and the RS-25 main engines, and shipment of the first flight hardware in preparation for the Exploration Flight Test-1 (EFT-1) in 2014. SLS was conceived with the goals of safety, affordability, and sustainability, while also providing unprecedented capability for human exploration and scientific discovery beyond Earth orbit. In an environment of economic challenges, the SLS team continues to meet ambitious budget and schedule targets through the studied use of hardware, infrastructure, and workforce investments the United States made in the last half century, while selectively using new technologies for design, manufacturing, and testing, as well as streamlined management approaches that have increased decision velocity and reduced associated costs. This paper will summarize recent SLS Program accomplishments, as well as the challenges and opportunities ahead for the most powerful and capable launch vehicle in history.

Developing Characterization Procedures for Qualifying both Novel Selective Laser Sintering Polymer Powders and Recycled Powders

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bajric, Sendin

Selective laser sintering (SLS) is an additive technique which is showing great promise over conventional manufacturing techniques. SLS requires certain key material properties for a polymer powder to be successfully processed into an end-use part, and therefore limited selection of materials are available. Furthermore, there has been evidence of a powder’s quality deteriorating following each SLS processing cycle. The current investigation serves to build a path forward in identifying new SLS powder materials by developing characterization procedures for identifying key material properties as well as for detecting changes in a powder’s quality. Thermogravimetric analyses, differential scanning calorimetry, and bulk densitymore » measurements were investigated.« less

STS-40 Spacelab Life Science 1 (SLS-1) module in OV-102's payload bay (PLB)

NASA Technical Reports Server (NTRS)

1991-01-01

STS-40 Spacelab Life Science 1 (SLS-1) module is documented in the payload bay (PLB) of Columbia, Orbiter Vehicle (OV) 102. Included in the view are: the spacelab (SL) transfer tunnel joggle section and support struts; SLS-1 module forward end cone with the European Space Agency (ESA) SL insignia, SLS-1 payload insignia, and the upper feed through plate (center); the orbiter maneuvering system (OMS) pods; and the vertical stabilizer with the Detailed Test Objective (DTO) 901 Shuttle Infrared Leeside Temperature Sensing (SILTS) at the top 24 inches. The vertical stabilizer is parallel to the Earth's limb which is highlighted by the sunlight at sunrise/sunset.

STS-40 Spacelab Life Science 1 (SLS-1) module in OV-102's payload bay (PLB)

NASA Technical Reports Server (NTRS)

1991-01-01

STS-40 Spacelab Life Science 1 (SLS-1) module is documented in the payload bay (PLB) of Columbia, Orbiter Vehicle (OV) 102. Included in the view are: the spacelab (SL) transfer tunnel joggle section and support struts; SLS-1 module forward end cone with the European Space Agency (ESA) SL insignia, SLS-1 payload insignia, and the upper feed through plate (center); the orbiter maneuvering system (OMS) pods; and the vertical stabilizer with the Detailed Test Objective (DTO) 901 Shuttle Infrared Leeside Temperature Sensing (SILTS) at the top 24 inches. The vertical stabilizer points to the Earth's limb and the cloud-covered surface of the Earth below.

Built to Explore MSFC-SLS-077

NASA Image and Video Library

2018-04-20

NASA's Space Launch System, the world's most powerful rocket, will enable a new era of exploration. With NASA's Orion spacecraft, SLS will launch astronauts on missions to the Moon, Mars and beyond. Exploration Mission-1, the first integrated flight of SLS and an uncrewed Orion, will be the first in a series of increasingly complex missions that will provide the foundation for human deep-space exploration and demonstrate NASA's commitment and capability to extend human existence beyond low-Earth orbit. Launching from NASA's Kennedy Space Center in Florida, the nation's premier multi-user spaceport, SLS will be the only rocket capable of sending crew and large cargo to the Moon in a single launch. (NASA/MSFC)

Streptolysin S-like virulence factors: the continuing sagA

PubMed Central

Molloy, Evelyn M.; Cotter, Paul D.; Hill, Colin; Mitchell, Douglas A.; Ross, R. Paul

2014-01-01

Streptolysin S (SLS) is a potent cytolytic toxin and virulence factor produced by nearly all Streptococcus pyogenes strains. Despite a 100-year history of research on this toxin, it has only recently been established that SLS represents the archetypal example of an extended family of post-translationally modified virulence factors also produced by some other streptococci and Gram-positive pathogens, such as Listeria monocytogenes and Clostridium botulinum. In this Review we describe the identification, genetics, biochemistry and various functions of SLS. We also discuss the shared features of the virulence-associated SLS-like peptides, as well as their place within the rapidly expanding family of thiazole/oxazole-modified microcins (TOMMs). PMID:21822292

Space Launch System Trans Lunar Payload Delivery Capability

NASA Technical Reports Server (NTRS)

Jackman, A. L.; Smith, D. A.

2016-01-01

NASA Marshall Space Flight Center (MSFC) has successfully completed the Critical Design Review (CDR) of the heavy lift Space Launch System (SLS) and is working towards first flight of the vehicle in 2018. SLS will begin flying crewed missions with an Orion to a lunar vicinity every year after the first 2 flights starting in the early 2020's. So as early as 2021 these Orion flights will deliver ancillary payload, termed "Co-Manifested Payload", with a mass of at least 5.5 metric tons and volume up to 280 cubic meters to a cis-lunar destination. Later SLS flights have a goal of delivering as much as 10 metric tons to a cis-lunar destination. This presentation will describe the ground and flight accommodations, interfaces, and resources planned to be made available to Co-Manifested Payload providers as part of the SLS system. An additional intention is to promote a two-way dialogue between vehicle developers and potential payload users in order to most efficiently evolve required SLS capabilities to meet diverse payload requirements.

Bioconversion of rice straw into a soil-like substrate

NASA Astrophysics Data System (ADS)

Yu, Chengying; Liu, Hong; Xing, Yidong; Manukovsky, N. S.; Kovalev, V. S.; Gurevich, Yu. L.

To increase the closure of bioregenerative life support systems (BLSS), the bioconversion of rice straw into a soil-like substrate (SLS) by mushrooms and worms has been studied. The results showed that rice straw could be treated better by aerobic fermentation and succeeding growth of mushrooms Pleurotus ostreatus. In this process the total content of lignocellulose in the straw was removed by 37.74%. Furthermore, 46.68 g (fresh weight) of mushrooms could be produced from 100.0 g (dry weight) of rice straw. During the conversion of rice straw into a starting SLS by mushrooms and worms, the matter loss was 77.31%. The lettuce has been planted in the SLS and the yield when lettuce was cultivated on the SLS (8.77gm-2day-1) was comparable to the yield obtained on the nutrient solution. In addition, the silicon in the SLS ash can reach upto 32% and the circulation of it is expected during the growth of rice.

Trajectory Dispersed Vehicle Process for Space Launch System

NASA Technical Reports Server (NTRS)

Statham, Tamara; Thompson, Seth

2017-01-01

The Space Launch System (SLS) vehicle is part of NASA's deep space exploration plans that includes manned missions to Mars. Manufacturing uncertainties in design parameters are key considerations throughout SLS development as they have significant effects on focus parameters such as lift-off-thrust-to-weight, vehicle payload, maximum dynamic pressure, and compression loads. This presentation discusses how the SLS program captures these uncertainties by utilizing a 3 degree of freedom (DOF) process called Trajectory Dispersed (TD) analysis. This analysis biases nominal trajectories to identify extremes in the design parameters for various potential SLS configurations and missions. This process utilizes a Design of Experiments (DOE) and response surface methodologies (RSM) to statistically sample uncertainties, and develop resulting vehicles using a Maximum Likelihood Estimate (MLE) process for targeting uncertainties bias. These vehicles represent various missions and configurations which are used as key inputs into a variety of analyses in the SLS design process, including 6 DOF dispersions, separation clearances, and engine out failure studies.

1300906

NASA Image and Video Library

2013-08-05

MORE THAN 250 PEOPLE FROM ACROSS NASA'S MARSHALL SPACE FLIGHT CENTER PARTICIPATED IN THE SPACE LAUNCH SYSTEM (SLS) POST-PRELIMINARY DESIGN REVIEW REPORT, HELD AUG. 5 IN ACTIVITIES BUILDING 4316. DISCUSSING THE REVIEW AND THANKING THE MARSHALL TEAM FOR A JOB WELL DONE, ARE FROM LEFT, GARRY LYLES, SLS CHIEF ENGINEER; TODD MAY, MANAGER OF THE SLS PROGRAM; STEVE CASH, DIRECTOR OF MARSHALL’S SAFETY & MISSION ASSURANCE DIRECTORATE; AND CHRIS SINGER, MANAGER OF MARSHALL’S ENGINEERING DIRECTORATE

Spacelab Life Sciences 1: Reprints of Background Life Sciences Publications

NASA Technical Reports Server (NTRS)

White, Ronald (Editor); Leonard, Joel I. (Editor)

1991-01-01

The research being conducted on SLS-1 is primarily concerned with the short-term adaptation of physiological systems to weightlessness. A comprehensive overview of the various disciplines being studied on SLS-1 is presented. Citations and abstracts of all the papers submitted by the SLS-1 investigator teams are contained. The physiological systems studied include: cardiovascular and cardiopulmonary, musculoskeletal, neurovestibular, renal and endocrine, hematological, and immunological.

STS-40 Payload Specialist Millie Hughes-Fulford trains in JSC's SLS mockup

NASA Image and Video Library

1987-03-10

STS-40 Payload Specialist Millie Hughes-Fulford conducts Spacelab Life Sciences 1 (SLS-1) Experiment No. 198, Pulmonary Function During Weightlessness, in JSC's Life Sciences Project Division (LSPD) SLS mockup located in the Bioengineering and Test Support Facility Bldg 36. Hughes-Fulford sets switches on Rack 8. Behind her in the center aisle are the stowed bicycle ergometer (foreground) and the body restraint system.

JCL Implementation On A Human Spaceflight Program

NASA Technical Reports Server (NTRS)

Kulpa, Vyga; Karpowich, Mike; Abel, Diana; Archiable, Wes; Carson, William

2013-01-01

Joint Confidence Level (JCL) analysis focuses on the integration of traditionally stove-piped programmatic components (schedule, cost and risk) to establish projected resource and schedule requirements at various confidence levels and to identify programmatic cost and schedule risk drivers. SLS Program consists of multiple Prime Contractors managed by independent SLS Elements which are integrated using SE&I and Program Management. SLS further integrates with GSDO and MPCV through ESD integrated working groups.

Characterization of Amorphous and Co-Amorphous Simvastatin Formulations Prepared by Spray Drying.

PubMed

Craye, Goedele; Löbmann, Korbinian; Grohganz, Holger; Rades, Thomas; Laitinen, Riikka

2015-12-03

In this study, spray drying from aqueous solutions, using the surface-active agent sodium lauryl sulfate (SLS) as a solubilizer, was explored as a production method for co-amorphous simvastatin-lysine (SVS-LYS) at 1:1 molar mixtures, which previously have been observed to form a co-amorphous mixture upon ball milling. In addition, a spray-dried formulation of SVS without LYS was prepared. Energy-dispersive X-ray spectroscopy (EDS) revealed that SLS coated the SVS and SVS-LYS particles upon spray drying. X-ray powder diffraction (XRPD) and differential scanning calorimetry (DSC) showed that in the spray-dried formulations the remaining crystallinity originated from SLS only. The best dissolution properties and a "spring and parachute" effect were found for SVS spray-dried from a 5% SLS solution without LYS. Despite the presence of at least partially crystalline SLS in the mixtures, all the studied formulations were able to significantly extend the stability of amorphous SVS compared to previous co-amorphous formulations of SVS. The best stability (at least 12 months in dry conditions) was observed when SLS was spray-dried with SVS (and LYS). In conclusion, spray drying of SVS and LYS from aqueous surfactant solutions was able to produce formulations with improved physical stability for amorphous SVS.

NASA Space Flight Vehicle Fault Isolation Challenges

NASA Technical Reports Server (NTRS)

Bramon, Christopher; Inman, Sharon K.; Neeley, James R.; Jones, James V.; Tuttle, Loraine

2016-01-01

The Space Launch System (SLS) is the new NASA heavy lift launch vehicle and is scheduled for its first mission in 2017. The goal of the first mission, which will be uncrewed, is to demonstrate the integrated system performance of the SLS rocket and spacecraft before a crewed flight in 2021. SLS has many of the same logistics challenges as any other large scale program. Common logistics concerns for SLS include integration of discrete programs geographically separated, multiple prime contractors with distinct and different goals, schedule pressures and funding constraints. However, SLS also faces unique challenges. The new program is a confluence of new hardware and heritage, with heritage hardware constituting seventy-five percent of the program. This unique approach to design makes logistics concerns such as testability of the integrated flight vehicle especially problematic. The cost of fully automated diagnostics can be completely justified for a large fleet, but not so for a single flight vehicle. Fault detection is mandatory to assure the vehicle is capable of a safe launch, but fault isolation is another issue. SLS has considered various methods for fault isolation which can provide a reasonable balance between adequacy, timeliness and cost. This paper will address the analyses and decisions the NASA Logistics engineers are making to mitigate risk while providing a reasonable testability solution for fault isolation.

Effects of different base agents on prediction of skin irritation by sodium lauryl sulfate using patch testing and repeated application test.

PubMed

Horita, Kotomi; Horita, Daisuke; Tomita, Hiroyuki; Yasoshima, Mitsue; Yagami, Akiko; Matsunaga, Kayoko

2017-05-01

Animal testing for cosmetics was banned in the European Union (EU) in 2013; therefore, human tests to predict and ensure skin safety such as the patch test or usage test are now in demand in Japan as well as in the EU. In order to investigate the effects of different bases on the findings of tests to predict skin irritation, we performed patch testing (PT) and the repeated application test (RAT) using sodium lauryl sulfate (SLS), a well-known irritant, dissolved in 6 different base agents to examine the effects of these bases on skin irritation by SLS. The bases for PT were distilled water, 50% ethanol, 100% ethanol, a gel containing 50% ethanol, white petrolatum, and hydrophilic cream. The concentrations of SLS were 0.2% and 0.5%. Twelve different base combinations were applied to the normal back skin of 19 individuals for 24h. RAT was performed with distilled water, 50% ethanol, 100% ethanol, a gel containing 50% ethanol, white petrolatum, and hydrophilic cream containing SLS at concentrations of 0.2%, 2%, and 5%, being applied to the arms of the same PT subjects. The test preparation of each base was applied at the same site, with 0.2% SLS being used in the first week, 2% SLS in the following week, and 5% SLS in the final week. The results of PT revealed that skin irritation scores varied when SLS at the same concentration was dissolved in a different base. The results of RAT showed that although skin irritation appeared with every base at a concentration of 5%, the positive rate was approximately the same. In conclusion, our results suggest that skin irritation elicited in PT depends on the base, while in RAT, it does not depend on the type of base employed. Copyright © 2017 Elsevier B.V. All rights reserved.

Enabling Science and Deep Space Exploration through Space Launch System (LSL) Secondary Payload Opportunities

NASA Technical Reports Server (NTRS)

Singer, Jody; Pelfrey, Joseph; Norris, George

2016-01-01

For the first time in almost 40 years, a NASA human-rated launch vehicle has completed its Critical Design Review (CDR). By reaching this milestone, NASA's Space Launch System (SLS) and Orion spacecraft are on the path to launch a new era of deep space exploration. NASA is making investments to expand science and exploration capability of the SLS by developing the capability to deploy small satellites during the trans-lunar phase of the mission trajectory. Exploration Mission 1 (EM-1), currently planned for launch no earlier than July 2018, will be the first mission to carry such payloads on the SLS. The EM-1 launch will include thirteen 6U Cubesat small satellites that will be deployed beyond low earth orbit. By providing an earth-escape trajectory, opportunities are created for advancement of small satellite subsystems, including deep space communications and in-space propulsion. This SLS capability also creates low-cost options for addressing existing Agency strategic knowledge gaps and affordable science missions. A new approach to payload integration and mission assurance is needed to ensure safety of the vehicle, while also maintaining reasonable costs for the small payload developer teams. SLS EM-1 will provide the framework and serve as a test flight, not only for vehicle systems, but also payload accommodations, ground processing, and on-orbit operations. Through developing the requirements and integration processes for EM-1, NASA is outlining the framework for the evolved configuration of secondary payloads on SLS Block upgrades. The lessons learned from the EM-1 mission will be applied to processes and products developed for future block upgrades. In the heavy-lift configuration of SLS, payload accommodations will increase for secondary opportunities including small satellites larger than the traditional Cubesat class payload. The payload mission concept of operations, proposed payload capacity of SLS, and the payload requirements for launch and deployment will be described to provide potential payload users an understanding of this unique exploration capability.

NASA's Space Launch System: Affordability for Sustainability

NASA Technical Reports Server (NTRS)

May, Todd A.; Creech, Stephen D.

2012-01-01

The National Aeronautics and Space Administration's (NASA) Space Launch System (SLS) Program, managed at the Marshall Space Flight Center, is charged with delivering a new capability for human exploration beyond Earth orbit in an austere economic climate. But the SLS value is clear and codified in United States (U.S.) budget law. The SLS Program knows that affordability is the key to sustainability and will provide an overview of initiatives designed to fit within the funding guidelines by using existing engine assets and hardware now in testing to meet a first launch by 2017 within the projected budget. It also has a long-range plan to keep the budget flat, yet evolve the 70-tonne (t) initial lift capability to 130-t lift capability after the first two flights. To achieve the evolved configuration, advanced technologies must offer appropriate return on investment to be selected through the competitive process. For context, the SLS will be larger than the Saturn V that took 12 men on 6 trips for a total of 11 days on the lunar surface some 40 years ago. Astronauts train for long-duration voyages on platforms such as the International Space Station, but have not had transportation to go beyond Earth orbit in modern times, until now. To arrive at the launch vehicle concept, the SLS Program conducted internal engineering and business studies that have been externally validated by industry and reviewed by independent assessment panels. In parallel with SLS concept studies, NASA is now refining its mission manifest, guided by U.S. space policy and the Global Exploration Roadmap, which reflects the mutual goals of a dozen member nations. This mission planning will converge with a flexible heavy-lift rocket that can carry international crews and the air, water, food, and equipment they need for extended trips to asteroids and Mars. In addition, the SLS capability will accommodate very large science instruments and other payloads, using a series of modular fairings and adapters to configure the rocket for the mission. The SLS affordability plan includes streamlining interfaces, applying risk-based insight into contracted work, centralizing systems engineering and integration, and nurturing a learning culture where the question Why? is often asked and the answer "Because we've always done it that way" is rarely heard. The SLS Program will deliver affordable space transportation solutions for the Orion Multi-Purpose Cargo Vehicle s first autonomous certification flight in 2017, followed by a crewed flight in 2021. As this briefing will show, the SLS will offer a global infrastructure asset for robotic and human scouts of all nations.

Rituximab in the treatment of shrinking lung syndrome in systemic lupus erythematosus.

PubMed

Peñacoba Toribio, Patricia; Córica Albani, María Emilia; Mayos Pérez, Mercedes; Rodríguez de la Serna, Arturo

2014-01-01

Shrinking lung syndrome (SLS) is a rare manifestation of systemic lupus erythematosus. We report the case of a patient with non-responding SLS (neither to glucocorticoids nor immunosupresors), who showed remarkable improvement after the onset of treatment with rituximab. Although there is a little evidence, treatment with rituximab could be proposed in SLS when classical treatment fails. Copyright © 2013 Elsevier España, S.L. All rights reserved.

Fabrication, characterization and gas sensing studies of PPy/MWCNT/SLS nanocomposite

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tiwari, D. C., E-mail: dctiwari2001@yahoo.com; Atri, Priyanka, E-mail: dctiwari2001@yahoo.com; Sharma, R.

2014-04-24

Multiwall carbon nanotubes (MWCNT) coated with polypyrrole nanocomposite was prepared by in-situ chemical oxidative polymerization method in the presence of surfactant (SLS). The scanning electron microscope (SEM) pictures indicate the core shell structure of PPy/MWCNT/SLS nanocomposite. Nature of the prepared material was investigated by X-ray diffraction spectroscopy. This nanocomposite shows the excellent gas sensing behaviour for ammonia gas at 150 ppm and 300 ppm levels.

Analytical Approaches to Guide SLS Fault Management (FM) Development

NASA Technical Reports Server (NTRS)

Patterson, Jonathan D.

2012-01-01

Extensive analysis is needed to determine the right set of FM capabilities to provide the most coverage without significantly increasing the cost, reliability (FP/FN), and complexity of the overall vehicle systems. Strong collaboration with the stakeholders is required to support the determination of the best triggers and response options. The SLS Fault Management process has been documented in the Space Launch System Program (SLSP) Fault Management Plan (SLS-PLAN-085).

Destination: Space

NASA Image and Video Library

2016-05-20

RS-25 rocket engine No. 2059 is removed from the A-1 Test Stand at Stennis Space Center on May 19, 2016. The engine was tested March 10 on the stand and is ready for use on NASA’s new Space Launch System (SLS) vehicle. NASA is developing the SLS to carry humans deeper into space than ever before. The SLS core stage will be powered by four RS-25 engines. Engine No. 2059 is scheduled for use on the first crewed SLS mission, Exploration Mission-2, which will carry American astronauts beyond low-Earth orbit for the first time since 1972. The photo above shows the engine, as well as the yellow thrust frame adapter above it, which holds the engine in place for testing.

In-Flight Suppression of a De-Stabilized F/A-18 Structural Mode Using the Space Launch System Adaptive Augmenting Control System

NASA Technical Reports Server (NTRS)

Wall, John; VanZwieten, Tannen; Giiligan Eric; Miller, Chris; Hanson, Curtis; Orr, Jeb

2015-01-01

Adaptive Augmenting Control (AAC) has been developed for NASA's Space Launch System (SLS) family of launch vehicles and implemented as a baseline part of its flight control system (FCS). To raise the technical readiness level of the SLS AAC algorithm, the Launch Vehicle Adaptive Control (LVAC) flight test program was conducted in which the SLS FCS prototype software was employed to control the pitch axis of Dryden's specially outfitted F/A-18, the Full Scale Advanced Systems Test Bed (FAST). This presentation focuses on a set of special test cases which demonstrate the successful mitigation of the unstable coupling of an F/A-18 airframe structural mode with the SLS FCS.

NASA's Space Launch System: A Flagship for Exploration Beyond Earth's Orbit

NASA Technical Reports Server (NTRS)

May, Todd

2012-01-01

The National Aeronautics and Space Administration s (NASA) Space Launch System (SLS) Program, managed at the Marshall Space Flight Center, is making progress toward delivering a new capability for exploration beyond Earth orbit in an austere economic climate. This fact drives the SLS team to find innovative solutions to the challenges of designing, developing, fielding, and operating the largest rocket in history. To arrive at the current SLS plan, government and industry experts carefully analyzed hundreds of architecture options and arrived at the one clear solution to stringent requirements for safety, affordability, and sustainability over the decades that the rocket will be in operation. This paper will explore ways to fit this major development within the funding guidelines by using existing engine assets and hardware now in testing to meet a first launch by 2017. It will explain the SLS Program s long-range plan to keep the budget within bounds, yet evolve the 70 metric ton (t) initial lift capability to 130-t lift capability after the first two flights. To achieve the evolved configuration, advanced technologies must offer appropriate return on investment to be selected through a competitive process. For context, the SLS will be larger than the Saturn V that took 12 men on 6 trips for a total of 11 days on the lunar surface over 4 decades ago. Astronauts train for long-duration voyages on the International Space Station, but have not had transportation to go beyond Earth orbit in modern times, until now. NASA is refining its mission manifest, guided by U.S. Space Policy and the Global Exploration Roadmap. Launching the Orion Multi-Purpose Cargo Vehicle s first autonomous certification flight in 2017, followed by a crewed flight in 2021, the SLS will offer a robust way to transport international crews and the air, water, food, and equipment they need for extended trips to asteroids, Lagrange Points, and Mars. In addition, the SLS will accommodate high-priority science experiments. SLS affordability initiatives include streamlining interfaces, applying risk-based insight into contracted work, centralizing systems engineering and integration, and nurturing a learning culture that continually benchmarks its performance against successful ventures. As this paper will explain, the SLS is making measurable progress toward becoming a global infrastructure asset for robotic and human scouts of all nations by harnessing business and technological innovations to deliver sustainable solutions for space exploration.

NASA's Space Launch System: A Flagship for Exploration Beyond Earth's Orbit

NASA Technical Reports Server (NTRS)

May, Todd A.

2012-01-01

The National Aeronautics and Space Administration's (NASA) Space Launch System (SLS) Program, managed at the Marshall Space Flight Center, is making progress toward delivering a new capability for exploration beyond Earth orbit in an austere economic climate. This fact drives the SLS team to find innovative solutions to the challenges of designing, developing, fielding, and operating the largest rocket in history. To arrive at the current SLS plan, government and industry experts carefully analyzed hundreds of architecture options and arrived at the one clear solution to stringent requirements for safety, affordability, and sustainability over the decades that the rocket will be in operation. This paper will explore ways to fit this major development within the funding guidelines by using existing engine assets and hardware now in testing to meet a first launch by 2017. It will explain the SLS Program s long-range plan to keep the budget within bounds, yet evolve the 70 metric ton (t) initial lift capability to 130-t lift capability after the first two flights. To achieve the evolved configuration, advanced technologies must offer appropriate return on investment to be selected through a competitive process. For context, the SLS will be larger than the Saturn V that took 12 men on 6 trips for a total of 11 days on the lunar surface over 4 decades ago. Astronauts train for long-duration voyages on the International Space Station, but have not had transportation to go beyond Earth orbit in modern times, until now. NASA is refining its mission manifest, guided by U.S. Space Policy and the Global Exploration Roadmap. Launching the Orion Multi-Purpose Crew Vehicle s (MPCV s) first autonomous certification flight in 2017, followed by a crewed flight in 2021, the SLS will offer a robust way to transport international crews and the air, water, food, and equipment they need for extended trips to asteroids, Lagrange Points, and Mars. In addition, the SLS will accommodate high-priority science experiments. SLS affordability initiatives include streamlining interfaces, applying risk-based insight into contracted work, centralizing systems engineering and integration, and nurturing a learning culture that continually benchmarks its performance against successful ventures. As this paper will explain, the SLS is making measurable progress toward becoming a global infrastructure asset for robotic and human scouts of all nations by harnessing business and technological innovations to deliver sustainable solutions for space exploration.

Effectiveness of modified seminars as a teaching-learning method in pharmacology

PubMed Central

Palappallil, Dhanya Sasidharan; Sushama, Jitha; Ramnath, Sai Nathan

2016-01-01

Context: Student-led seminars (SLS) are adopted as a teaching-learning (T-L) method in pharmacology. Previous studies assessing the feedback on T-L methods in pharmacology points out that the traditional seminars consistently received poor feedbacks as they were not favorite among the students. Aims: This study aimed to obtain feedback on traditional SLS, introduce modified SLS and compare the modified seminars with the traditional ones. Settings and Design: This was a prospective interventional study done for 2 months in medical undergraduates of fifth semester attending Pharmacology seminars at a Government Medical College in South India. Subjects and Methods: Structured questionnaire was used to elicit feedback from participants. The responses were coded on 5-point Likert scale. Modifications in seminar sessions such as role plays, quiz, tests, group discussion, and patient-oriented problem-solving exercises were introduced along with SLS. Statistical Analysis Used: The data were analyzed using SPSS version 16. The descriptive data were expressed using frequencies and percentages. Wilcoxon signed rank test, and Friedman tests were used to compare traditional with modified seminars. Results: The participants identified interaction as the most important component of a seminar. Majority opined that the teacher should summarize at the end of SLS. Student feedback shows that modified seminars created more interest, enthusiasm, and inspiration to learn the topic when compared to traditional SLS. They also increased peer coordination and group dynamics. Students opined that communication skills and teacher-student interactions were not improved with modified seminars. Conclusions: Interventions in the form of modified SLS may be adopted to break the monotony of traditional seminars through active participation, peer interaction, and teamwork. PMID:27563587

NASA Space Launch System Operations Strategy

NASA Technical Reports Server (NTRS)

Singer, Joan A.; Cook, Jerry R.

2012-01-01

The National Aeronautics and Space Administration's (NASA) Space Launch System (SLS) Program, managed at the Marshall Space Flight Center, is charged with delivering a new capability for human and scientific exploration beyond Earth orbit. The SLS also will provide backup crew and cargo services to the International Space Station, where astronauts have been training for long-duration voyages to destinations such as asteroids and Mars. For context, the SLS will be larger than the Saturn V, providing 10 percent more thrust at liftoff in its initial 70 metric ton (t) configuration and 20 percent more in its evolved 130 t configuration. The SLS Program knows that affordability is the key to sustainability. This paper will provide an overview of its operations strategy, which includes initiatives to reduce both development and fixed costs by using existing hardware and infrastructure assets to meet a first launch by 2017 within the projected budget. It also has a long-range plan to keep the budget flat using competitively selected advanced technologies that offer appropriate return on investment. To arrive at the launch vehicle concept, the SLS Program conducted internal engineering and business studies that have been externally validated by industry and reviewed by independent assessment panels. A series of design reference missions has informed the SLS operations concept, including launching the Orion Multi-Purpose Crew Vehicle on an autonomous demonstration mission in a lunar flyby scenario in 2017, and the first flight of a crew on Orion for a lunar flyby in 2021. Additional concepts address the processing of very large payloads, using a series of modular fairings and adapters to flexibly configure the rocket for the mission. This paper will describe how the SLS, Orion, and 21st Century Ground Systems programs are working together to create streamlined, affordable operations for sustainable exploration.

Functional heterogeneity and outcomes in community-dwelling women with osteoporosis, with and without a history of falls.

PubMed

Pua, Yong-Hao; Ong, Peck-Hoon; Lim, Edwin Choon-Wyn; Huang, Katherin Shilin; Clark, Ross A; Chandran, Manju

2014-03-01

Falls leading to osteoporotic fracture is a substantial issue clinically. By inference from the literature, women with osteoporosis who are classified as having a history of falls may not represent a distinct homogeneous population. However, studies exploring the potential heterogeneity within fallers in women with osteoporosis are scarce. The objective of this study was to better understand the physical function characteristics of women with osteoporosis, with and without a previous history of falls, by further stratifying them based on their single-leg stance (SLS) performance. Eighty-seven consecutive, community-dwelling women with osteoporosis were recruited from the Endocrinology Clinic at Singapore General Hospital. Laboratory-based and clinic-based standing balance tests, a lower limb strength test, and the 6-min walk test (6MWT) were measured. Fallers and non-fallers did not differ in standing balance, lower limb strength nor the 6MWT (P's>0.08). SLS performance was an independent predictor of the various functional measures, after adjusting for age and body mass index. Specifically, an increase in SLS time was associated with lower standing center-of-pressure velocities, greater lower limb strength, and greater 6-min walking distance. When the two groups were stratified based on their recent history of falls and clinic-based standing balance performance (SLS time), fallers with good SLS time (>30 s) showed better functional outcomes than did non-fallers with poor SLS time (≤30 s) (P's<0.08) and comparable functional outcomes with non-fallers with good SLS time (P's>0.11). The results indicate an important heterogeneity within fallers and non-fallers with osteoporosis and they argue for a individualized approach to rehabilitation. Copyright © 2013 Elsevier B.V. All rights reserved.

The MOAHLFA index of irritant sodium lauryl sulfate reactions: first results of a multicentre study on routine sodium lauryl sulfate patch testing.

PubMed

Uter, Wolfgang; Geier, Johannes; Becker, Detlef; Brasch, Jochen; Löffler, Harald

2004-01-01

In a multicentre study of the German Contact Dermatitis Research Group, sodium lauryl sulfate (SLS) 0.25% and 0.5% aq. has been added to routine allergen patch tests to assess its properties as a convenient diagnostic indicator of individual susceptibility to irritation at the time of patch testing. Previous studies indicated that irritant SLS reactivity may be related to individual factors such as age and sex. As these factors are, in turn, among the important predictors of contact allergy to many allergens, e.g. summarized in the 'MOAHLFA index', the impact of the MOAHLFA factors on irritant SLS patch test reactivity, and thus a potential for confounding, was assessed in the 5971 participating patients. As a result of 2 logistic regression analyses with an irritant reaction to 0.25% and 0.5% SLS, respectively, as outcome, male sex was identified as a relatively weak but significant risk factor (OR 1.38), while age 40 years or older was an even weaker risk factor (OR 1.22 and 1.15, respectively). Upon detailed analysis, no clear age gradient could, however, be identified. 1-day exposure time almost halved the odds of an irritant SLS reaction. In conclusion, this type of SLS patch test can be regarded as robust, indicating individual irritability relatively independent from the individual factors analysed here.

Surface-coated fly ash used as filler in biodegradable poly(vinyl alcohol) composite films: Part 1—The modification process

NASA Astrophysics Data System (ADS)

Nath, D. C. D.; Bandyopadhyay, S.; Gupta, S.; Yu, A.; Blackburn, D.; White, C.

2010-02-01

The surfaces of fly ash (FA) particles were modified by surfactant, sodium lauryl sulphate (SLS) and used in fabrication of composite films with polyvinyl alcohol (PVA). Both unmodified fly ash (FA) and modified fly ash (SLS-FA) samples were examined using a range of analytical tools including X-ray fluorescence spectroscopy (XRF), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) and X-ray photoelectron spectroscopy (XPS). The distribution patterns of SLS-FA particles were shifted to the higher regions compared to FA by adding 1.2-4.2 μm in the ranges between 2 and 25 μm, whereas the modification process reduced the size of the particles over 25 μm due to grinding during the activation process. The increased 1.2-4.2 μm in average can be considered the thickness of the surfactant on the SLS-FA surface. On the oxides based chemical analysis by XRF, the compositions were almost unchanged. SEM and TEM were visualised the irregular sizes morphology mostly spherical of the particles, although it is impossible to capture the images of exactly same particles in modified and unmodified forms. The composite films reinforced with SLS-FA showed 33% higher strength than those of FA filled films. The enhancement of tensile strength attributed from the level of physical bonding between SLS-FA and PVA surfaces.

Silica-coated flexible liposomes as a nanohybrid delivery system for enhanced oral bioavailability of curcumin

PubMed Central

Li, Chong; Zhang, Yan; Su, Tingting; Feng, Lianlian; Long, Yingying; Chen, Zhangbao

2012-01-01

We investigated flexible liposomes as a potential oral drug delivery system. However, enhanced membrane fluidity and structural deformability may necessitate liposomal surface modification when facing the harsh environment of the gastrointestinal tract. In the present study, silica-coated flexible liposomes loaded with curcumin (CUR-SLs) having poor water solubility as a model drug were prepared by a thin-film method with homogenization, followed by the formation of a silica shell by the sol-gel process. We systematically investigated the physical properties, drug release behavior, pharmacodynamics, and bioavailability of CUR-SLs. CUR-SLs had a mean diameter of 157 nm and a polydispersity index of 0.14, while the apparent entrapment efficiency was 90.62%. Compared with curcumin-loaded flexible liposomes (CUR-FLs) without silica-coatings, CUR-SLs had significantly higher stability against artificial gastric fluid and showed more sustained drug release in artificial intestinal fluid as determined by in vitro release assays. The bioavailability of CUR-SLs and CUR-FLs was 7.76- and 2.35-fold higher, respectively, than that of curcumin suspensions. Silica coating markedly improved the stability of flexible liposomes, and CUR-SLs exhibited a 3.31-fold increase in bioavailability compared with CUR-FLs, indicating that silica-coated flexible liposomes may be employed as a potential carrier to deliver drugs with poor water solubility via the oral route with improved bioavailability. PMID:23233804

Silica-coated flexible liposomes as a nanohybrid delivery system for enhanced oral bioavailability of curcumin.

PubMed

Li, Chong; Zhang, Yan; Su, Tingting; Feng, Lianlian; Long, Yingying; Chen, Zhangbao

2012-01-01

We investigated flexible liposomes as a potential oral drug delivery system. However, enhanced membrane fluidity and structural deformability may necessitate liposomal surface modification when facing the harsh environment of the gastrointestinal tract. In the present study, silica-coated flexible liposomes loaded with curcumin (CUR-SLs) having poor water solubility as a model drug were prepared by a thin-film method with homogenization, followed by the formation of a silica shell by the sol-gel process. We systematically investigated the physical properties, drug release behavior, pharmacodynamics, and bioavailability of CUR-SLs. CUR-SLs had a mean diameter of 157 nm and a polydispersity index of 0.14, while the apparent entrapment efficiency was 90.62%. Compared with curcumin-loaded flexible liposomes (CUR-FLs) without silica-coatings, CUR-SLs had significantly higher stability against artificial gastric fluid and showed more sustained drug release in artificial intestinal fluid as determined by in vitro release assays. The bioavailability of CUR-SLs and CUR-FLs was 7.76- and 2.35-fold higher, respectively, than that of curcumin suspensions. Silica coating markedly improved the stability of flexible liposomes, and CUR-SLs exhibited a 3.31-fold increase in bioavailability compared with CUR-FLs, indicating that silica-coated flexible liposomes may be employed as a potential carrier to deliver drugs with poor water solubility via the oral route with improved bioavailability.

Increased intestinal absorption in the rat caused by sodium lauryl sulphate, and its possible relation to the cAMP system.

PubMed

Briseid, G; Briseid, K; Kirkevold, K

1976-01-01

The increases in the absorption of ouabain, phenolsulphonphthalein and pralidoxime caused by 17 mM sodium lauryl sulphate (SLS) from jejunal loops of anaesthetized rats were significantly reduced if sodium and chloride (Briseid et al., 1974) or chloride and bicarbonate were replaced by other ions in the loop fluid. Separate substitutions of sodium, chloride of bicarbonate did not significantly alter the SLS-caused absorption, except that the substitution of choline for sodium reduced the absorption of pralidoxime, both in the presence and in the absence of SLS. The increases in the absorption of phenolsulphonphthalein and pralidoxime caused by SLS were potentiated by theophylline (25 mM) and reduced by imidazole (25 mM). The addition of dibutyryl cyclic AMP (2.5 mM) to the loop fluid increased this absorption of the test substances. This effect was reduced by imidazole, but under the experimental conditions it was not potentiated by theophylline. Determinations of cyclic AMP in the rat intestinal mucosa showed that the level of this substance was significantly higher in the presence than in the absence of SLS. The experimental conditions were as described for the absorption experiments. It is concluded that the data obtained support the idea of an increased level of cyclic AMP as the main basis for the effect of SLS on the absorption.

Strigolactones in the Rhizobium-legume symbiosis: Stimulatory effect on bacterial surface motility and down-regulation of their levels in nodulated plants.

PubMed

Peláez-Vico, María A; Bernabéu-Roda, Lydia; Kohlen, Wouter; Soto, María J; López-Ráez, Juan A

2016-04-01

Strigolactones (SLs) are multifunctional molecules acting as modulators of plant responses under nutrient deficient conditions. One of the roles of SLs is to promote beneficial association with arbuscular mycorrhizal (AM) fungi belowground under such stress conditions, mainly phosphorus shortage. Recently, a role of SLs in the Rhizobium-legume symbiosis has been also described. While SLs' function in AM symbiosis is well established, their role in the Rhizobium-legume interaction is still emerging. Recently, SLs have been suggested to stimulate surface motility of rhizobia, opening the possibility that they could also act as molecular cues. The possible effect of SLs in the motility in the alfalfa symbiont Sinorhizobium meliloti was investigated, showing that the synthetic SL analogue GR24 stimulates swarming motility in S. meliloti in a dose-dependent manner. On the other hand, it is known that SL production is regulated by nutrient deficient conditions and by AM symbiosis. Using the model alfalfa-S. meliloti, the impact of phosphorus and nitrogen deficiency, as well as of nodulation on SL production was also assessed. The results showed that phosphorus starvation promoted SL biosynthesis, which was abolished by nitrogen deficiency. In addition, a negative effect of nodulation on SL levels was detected, suggesting a conserved mechanism of SL regulation upon symbiosis establishment. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

The reliability and criterion validity of 2D video assessment of single leg squat and hop landing.

PubMed

Herrington, Lee; Alenezi, Faisal; Alzhrani, Msaad; Alrayani, Hasan; Jones, Richard

2017-06-01

The objective was to assess the intra-tester, within and between day reliability of measurement of hip adduction (HADD) and frontal plane projection angles (FPPA) during single leg squat (SLS) and single leg landing (SLL) using 2D video and the validity of these measurements against those found during 3D motion capture. 15 healthy subjects had their SLS and SLL assessed using 3D motion capture and video analysis. Inter-tester reliability for both SLS and SLL when measuring FPPA and HADD show excellent correlations (ICC 2,1 0.97-0.99). Within and between day assessment of SLS and SLL showed good to excellent correlations for both variables (ICC 3,1 0.72-91). 2D FPPA measures were found to have good correlation with knee abduction angle in 3-D (r=0.79, p=0.008) during SLS, and also to knee abduction moment (r=0.65, p=0.009). 2D HADD showed very good correlation with 3D HADD during SLS (r=0.81, p=0.001), and a good correlation during SLL (r=0.62, p=0.013). All other associations were weak (r<0.4). This study suggests that 2D video kinematics have a reasonable association to what is being measured with 3D motion capture. Copyright © 2017 Elsevier Ltd. All rights reserved.

Simultaneous Isolation of Lactoferrin and Lactoperoxidase from Bovine Colostrum by SPEC 70 SLS Cation Exchange Resin

PubMed Central

Liang, Yafei; Wang, Xuewan; Wu, Mianbin; Zhu, Wanping

2011-01-01

In this work, simultaneous isolation of lactoferrin (Lf) and lactoperoxidase (Lp) from defatted bovine colostrum by one-step cation exchange chromatography with SPEC 70 SLS ion-exchange resin was investigated. A RP-HPLC method for Lf and Lp determination was developed and optimized as the following conditions: detection wavelength of 220 nm, flow rate of 1 mL/min and acetonitrile concentration from 25% to 75% within 20 min. The adsorption process of Lf on SPEC 70 SLS resin was optimized using Lf standard as substrate. The maximum static binding capacity of SPEC 70 SLS resin was of 22.0 mg/g resin at 15 °C, pH 7.0 and adsorption time 3 h. The Lf adsorption process could be well described by the Langmuir adsorption isotherm model, with a maximum adsorption capacity of 21.73 mg/g resin at 15 °C. In batch fractionation of defatted colostrum, the binding capacities of SPEC 70 SLS resin for adsorbing Lf and Lp simultaneously under the abovementioned conditions were 7.60 and 6.89 mg/g resin, respectively, both of which were superior to those of CM Sepharose F.F. or SP Sepharose F.F. resins under the same conditions. As a result, SPEC 70 SLS resin was considered as a successful candidate for direct and economic purification of Lf and Lp from defatted colostrum. PMID:22016715

Detector and readout performance goals for quantum well and strained layer superlattice focal plane arrays imaging under tactical and strategic backgrounds

NASA Astrophysics Data System (ADS)

Bandara, Sumith V.

2009-11-01

Advancements in III-V semiconductor based, Quantum-well infrared photodetector (QWIP) and Type-II Strained-Layer Superlattice detector (T2SLS) technologies have yielded highly uniform, large-format long-wavelength infrared (LWIR) QWIP FPAs and high quantum efficiency (QE), small format, LWIR T2SLS FPAs. In this article, we have analyzed the QWIP and T2SLS detector level performance requirements and readout integrated circuit (ROIC) noise levels for several staring array long-wavelength infrared (LWIR) imaging applications at various background levels. As a result of lower absorption QE and less than unity photoconductive gain, QWIP FPAs are appropriate for high background tactical applications. However, if the application restricts the integration time, QWIP FPA performance may be limited by the read noise of the ROIC. Rapid progress in T2SLS detector material has already demonstrated LWIR detectors with sufficient performance for tactical applications and potential for strategic applications. However, significant research is needed to suppress surface leakage currents in order to reproduce performances at pixel levels of T2SLS FPAs.

Strigolactones Stimulate Internode Elongation Independently of Gibberellins1[C][W

PubMed Central

de Saint Germain, Alexandre; Ligerot, Yasmine; Dun, Elizabeth A.; Pillot, Jean-Paul; Ross, John J.; Beveridge, Christine A.; Rameau, Catherine

2013-01-01

Strigolactone (SL) mutants in diverse species show reduced stature in addition to their extensive branching. Here, we show that this dwarfism in pea (Pisum sativum) is not attributable to the strong branching of the mutants. The continuous supply of the synthetic SL GR24 via the root system using hydroponics can restore internode length of the SL-deficient rms1 mutant but not of the SL-response rms4 mutant, indicating that SLs stimulate internode elongation via RMS4. Cytological analysis of internode epidermal cells indicates that SLs control cell number but not cell length, suggesting that SL may affect stem elongation by stimulating cell division. Consequently, SLs can repress (in axillary buds) or promote (in the stem) cell division in a tissue-dependent manner. Because gibberellins (GAs) increase internode length by affecting both cell division and cell length, we tested if SLs stimulate internode elongation by affecting GA metabolism or signaling. Genetic analyses using SL-deficient and GA-deficient or DELLA-deficient double mutants, together with molecular and physiological approaches, suggest that SLs act independently from GAs to stimulate internode elongation. PMID:23943865

Propulsion Progress for NASA's Space Launch System

NASA Technical Reports Server (NTRS)

May, Todd A.; Lyles, Garry M.; Priskos, Alex S.; Kynard, Michael H.; Lavoie, Anthony R.

2012-01-01

Leaders from NASA's Space Launch System (SLS) will participate in a panel discussing the progress made on the program's propulsion systems. The SLS will be the nation's next human-rated heavy-lift vehicle for new missions beyond Earth's orbit. With a first launch slated for 2017, the SLS Program is turning plans into progress, with the initial rocket being built in the U.S.A. today, engaging the aerospace workforce and infrastructure. Starting with an overview of the SLS mission and programmatic status, the discussion will then delve into progress on each of the primary SLS propulsion elements, including the boosters, core stage engines, upper stage engines, and stage hardware. Included will be a discussion of the 5-segment solid rocket motors (ATK), which are derived from Space Shuttle and Ares developments, as well as the RS-25 core stage engines from the Space Shuttle inventory and the J- 2X upper stage engine now in testing (Pratt and Whitney Rocketdyne). The panel will respond to audience questions about this important national capability for human and scientific space exploration missions.

Streptococcus iniae beta-hemolysin streptolysin S is a virulence factor in fish infection.

PubMed

Locke, Jeffrey B; Colvin, Kelly M; Varki, Nissi; Vicknair, Mike R; Nizet, Victor; Buchanan, John T

2007-06-07

Streptococcus iniae is a leading pathogen of intensive aquaculture operations worldwide, although understanding of virulence mechanisms of this pathogen in fish is lacking. S. iniae possesses a homolog of streptolysin S (SLS), a secreted, pore-forming cytotoxin that is a proven virulence factor in the human pathogen S. pyogenes. Here we used allelic exchange mutagenesis of the structural gene for the S. iniae SLS precursor (sagA) to examine the role of SLS in S. iniae pathogenicity using in vitro and in vivo models. The isogenic Delta sagA mutant was less cytotoxic to fish blood cells and cultured epithelial cells, but comparable to wild-type (WT) S. iniae in adherence/invasion of epithelial cell monolayers and resisting phagocytic killing by fish whole blood or macrophages. In a hybrid striped bass infection model, loss of SLS production led to marked virulence attenuation, as injection of the Delta sagA mutant at 1000x the WT lethal dose (LD80) produced only 10% mortality. The neutralization of SLS could represent a novel strategy for control of S. iniae infection in aquaculture.

Canker Sores

MedlinePlus

... Sodium lauryl sulfate (SLS), an ingredient in many toothpastes and mouthwashes, has been linked to canker sores, ... you brush your teeth . Brush and rinse with toothpastes and mouthwashes that don't contain SLS. And ...

Allergic contact dermatitis from ophthalmic products: can pre-treatment with sodium lauryl sulfate increase patch test sensitivity?

PubMed

Corazza, Monica; Virgili, Annarosa

2005-05-01

In patients suspected of allergic contact dermatitis because of topical ophthalmic medicaments, patch tests performed with patients' own products are often negative. The irritant anionic surfactant sodium lauryl sulfate (SLS) may alter the stratum corneum and increase antigen penetration. Pre-treatment of the skin with SLS 0.5% for 24 h was performed in the sites of patch tests with patients' own products in 15 selected patients. In patients previously negative to their own products tested with conventional patch tests, SLS pre-treatment showed 6 new relevant positive reactions and induced a stronger positive reaction in 1 patient. SLS pre-treatment could be proposed as an alternative promising method, which may increase sensitivity of patch tests with patients' own products.

KSC-2011-7779

NASA Image and Video Library

2011-11-15

CAPE CANAVERAL, Fla. – At NASA's Kennedy Space Center in Florida, the mobile launcher (ML) is being prepared for its move aboard a crawler-transporter from next to Kennedy's Vehicle Assembly Building to Launch Pad 39B, a distance of 4.2 miles. Data on the ML will be collected from structural and functional engineering tests and used for the next phases of construction. The 355-foot-tall ML, which took about two years to construct, is being modified to support NASA's Space Launch System (SLS), the heavy-lift rocket that will launch astronauts farther into space than ever before. SLS will also create high-quality jobs here at home, and provide the cornerstone for America's future human space exploration efforts. For more information on SLS, visit http://www.nasa.gov/sls. Photo credit: NASA/Kim Shiflett

KSC-2011-7777

NASA Image and Video Library

2011-11-15

CAPE CANAVERAL, Fla. – At NASA's Kennedy Space Center in Florida, the mobile launcher (ML) is being prepared for its move aboard a crawler-transporter from next to Kennedy's Vehicle Assembly Building to Launch Pad 39B, a distance of 4.2 miles. Data on the ML will be collected from structural and functional engineering tests and used for the next phases of construction. The 355-foot-tall ML, which took about two years to construct, is being modified to support NASA's Space Launch System (SLS), the heavy-lift rocket that will launch astronauts farther into space than ever before. SLS will also create high-quality jobs here at home, and provide the cornerstone for America's future human space exploration efforts. For more information on SLS, visit http://www.nasa.gov/sls. Photo credit: NASA/Kim Shiflett

VAB Platform K(2) Lift & Install into Highbay 3

NASA Image and Video Library

2016-03-07

Work is underway to secure the second half of the K-level work platforms for NASA’s Space Launch System (SLS) rocket in High Bay 3 inside the Vehicle Assembly Building at NASA's Kennedy Space Center in Florida. The platform is being secured into position on tower E, about 86 feet above the floor. The K work platforms will provide access to NASA's Space Launch System (SLS) core stage and solid rocket boosters during processing and stacking operations on the mobile launcher. The Ground Systems Development and Operations Program is overseeing upgrades and modifications to High Bay 3 to support processing of the SLS and Orion spacecraft. A total of 10 levels of new platforms, 20 platform halves altogether, will surround the SLS rocket and Orion spacecraft.

VAB Platform K(2) Lift & Install into Highbay 3

NASA Image and Video Library

2016-03-07

A 250-ton crane is used to lower the second half of the K-level work platforms for NASA’s Space Launch System (SLS) rocket into High Bay 3 inside the Vehicle Assembly Building at NASA's Kennedy Space Center in Florida. The platform will be secured about 86 feet above the VAB floor, on tower E of the high bay. The K work platforms will provide access to the SLS core stage and solid rocket boosters during processing and stacking operations on the mobile launcher. The Ground Systems Development and Operations Program is overseeing upgrades and modifications to High Bay 3 to support processing of the SLS and Orion spacecraft. A total of 10 levels of new platforms, 20 platform halves altogether, will surround the SLS rocket and Orion spacecraft.

Deep Space Habitat Concept Demonstrator

NASA Technical Reports Server (NTRS)

Bookout, Paul S.; Smitherman, David

2015-01-01

This project will develop, integrate, test, and evaluate Habitation Systems that will be utilized as technology testbeds and will advance NASA's understanding of alternative deep space mission architectures, requirements, and operations concepts. Rapid prototyping and existing hardware will be utilized to develop full-scale habitat demonstrators. FY 2014 focused on the development of a large volume Space Launch System (SLS) class habitat (Skylab Gen 2) based on the SLS hydrogen tank components. Similar to the original Skylab, a tank section of the SLS rocket can be outfitted with a deep space habitat configuration and launched as a payload on an SLS rocket. This concept can be used to support extended stay at the Lunar Distant Retrograde Orbit to support the Asteroid Retrieval Mission and provide a habitat suitable for human missions to Mars.

KSC-2011-7778

NASA Image and Video Library

2011-11-15

CAPE CANAVERAL, Fla. – At NASA's Kennedy Space Center in Florida, the mobile launcher (ML) is being prepared for its move aboard a crawler-transporter from next to Kennedy's Vehicle Assembly Building to Launch Pad 39B, a distance of 4.2 miles. Data on the ML will be collected from structural and functional engineering tests and used for the next phases of construction. The 355-foot-tall ML, which took about two years to construct, is being modified to support NASA's Space Launch System (SLS), the heavy-lift rocket that will launch astronauts farther into space than ever before. SLS will also create high-quality jobs here at home, and provide the cornerstone for America's future human space exploration efforts. For more information on SLS, visit http://www.nasa.gov/sls. Photo credit: NASA/Kim Shiflett

KSC-2011-7780

NASA Image and Video Library

2011-11-15

CAPE CANAVERAL, Fla. – At NASA's Kennedy Space Center in Florida, the mobile launcher (ML) is being prepared for its move aboard a crawler-transporter from next to Kennedy's Vehicle Assembly Building to Launch Pad 39B, a distance of 4.2 miles. Data on the ML will be collected from structural and functional engineering tests and used for the next phases of construction. The 355-foot-tall ML, which took about two years to construct, is being modified to support NASA's Space Launch System (SLS), the heavy-lift rocket that will launch astronauts farther into space than ever before. SLS will also create high-quality jobs here at home, and provide the cornerstone for America's future human space exploration efforts. For more information on SLS, visit http://www.nasa.gov/sls. Photo credit: NASA/Kim Shiflett

Preparing for Flight Engine Test

NASA Image and Video Library

2015-11-04

The first RS-25 flight engine, engine No. 2059, is lifted onto the A-1 Test Stand at Stennis Space Center on Nov. 4, 2015. The engine was tested in early 2016 to certify it for use on NASA’s new Space Launch System (SLS). The SLS core stage will be powered by four RS-25 engines, all tested at Stennis Space Center. NASA is developing the SLS to carry humans deeper into space than ever before, including on a journey to Mars.

SLS EM-1 Launch Animation

NASA Image and Video Library

2017-10-31

Animation depicting NASA’s Space Launch System, the world's most powerful rocket for a new era of human exploration beyond Earth’s orbit. With its unprecedented capabilities, SLS will launch astronauts in the agency’s Orion spacecraft on missions to explore multiple, deep-space destinations, including Mars. Traveling to deep space requires a large vehicle that can carry huge payloads, and future evolutions of SLS with the exploration upper stage and advanced boosters will increase the rocket’s lift capability and flexibility for multiple types of mission needs.

STS-40 Spacelab Life Science 1 (SLS-1) module in OV-102's payload bay (PLB)

NASA Image and Video Library

1991-06-14

STS040-610-010 (5-14 June 1991) --- The blue and white Earth forms the backdrop for this scene of the Spacelab Life Sciences (SLS-1) module in the cargo bay of the Earth-orbiting Columbia. The view was photographed through Columbia's aft flight deck windows with a handheld Rolleiflex camera. Seven crewmembers spent nine days in space aboard Columbia. Part of the tunnel/airlock system that linked them to the SLS-1 module is seen in center foreground.

Sjogren-Larsson Syndrome

MedlinePlus

... beneficial in the treatment of SLS. In these studies, the drug successfully reduced the severity of the pruritis (itching), and improved the behavior of the treated child. While this drug does not cure SLS, it ...

NASA's Space Launch System: A Heavy-Lift Platform for Entirely New Missions

NASA Technical Reports Server (NTRS)

Creech, Stephen D.

2012-01-01

The National Aeronautics and Space Administration's (NASA's) Space Launch System (SLS) will contribute a new capability for human space flight and scientific missions beyond low-Earth orbit (LEO). The SLS Program, managed at NASA s Marshall Space Flight Center, will develop the heavy-lift vehicle that will launch the Orion Multi-Purpose Crew Vehicle (MPCV), equipment, supplies, and major science missions for exploration and discovery. Orion will carry crews to space, provide emergency abort capability, sustain the crew during space travel, and provide safe reentry from deep-space return velocities. Supporting Orion s first autonomous flight to lunar orbit and back in 2017 and its first crewed flight in 2021, the SLS ultimately offers a flexible platform for both human and scientific exploration. The SLS plan leverages legacy infrastructure and hardware in NASA s inventory, as well as continues with advanced technologies now in development, to deliver an initial 70 metric ton (t) lift capability in 2017, evolving to a 130-t capability, using a block upgrade approach. This paper will give an overview of the SLS design and management approach against a backdrop of the missions it will support. It will detail the plan to deliver the initial SLS capability to the launch pad in the near term, as well as summarize the innovative approaches the SLS team is applying to deliver a safe, affordable, and sustainable long-range capability for entirely new missions-opening a new realm of knowledge and a world of possibilities for multiple partners. Design reference missions that the SLS is being planned to support include Mars, Jupiter, Lagrange Points, and near-Earth asteroids (NEAs), among others. The Agency is developing its mission manifest in parallel with the development of a heavy-lift flagship that will dramatically increase total lift and volume capacity beyond current launch vehicle options, reduce trip times, and provide a robust platform for conducting new missions destined to rewrite textbooks with the information they deliver, while creating a framework for further collaboration among domestic and international partners, and potentially spurring economic expansion into new markets.

NASA'S Space Launch System: Opening Opportunities for Mission Design

NASA Technical Reports Server (NTRS)

Robinson, Kimberly F.; Hefner, Keith; Hitt, David

2015-01-01

Designed to meet the stringent requirements of human exploration missions into deep space and to Mars, NASA's Space Launch System (SLS) vehicle represents a unique new launch capability opening new opportunities for mission design. While SLS's super-heavy launch vehicle predecessor, the Saturn V, was used for only two types of missions - launching Apollo spacecraft to the moon and lofting the Skylab space station into Earth orbit - NASA is working to identify new ways to use SLS to enable new missions or mission profiles. In its initial Block 1 configuration, capable of launching 70 metric tons (t) to low Earth orbit (LEO), SLS is capable of not only propelling the Orion crew vehicle into cislunar space, but also delivering small satellites to deep space destinations. With a 5-meter (m) fairing consistent with contemporary Evolved Expendable Launch Vehicles (EELVs), the Block 1 configuration can also deliver science payloads to high-characteristic-energy (C3) trajectories to the outer solar system. With the addition of an upper stage, the Block 1B configuration of SLS will be able to deliver 105 t to LEO and enable more ambitious human missions into the proving ground of space. This configuration offers opportunities for launching co-manifested payloads with the Orion crew vehicle, and a new class of secondary payloads, larger than today's cubesats. The evolved configurations of SLS, including both Block 1B and the 130 t Block 2, also offer the capability to carry 8.4- or 10-m payload fairings, larger than any contemporary launch vehicle. With unmatched mass-lift capability, payload volume, and C3, SLS not only enables spacecraft or mission designs currently impossible with contemporary EELVs, it also offers enhancing benefits, such as reduced risk and operational costs associated with shorter transit time to destination and reduced risk and complexity associated with launching large systems either monolithically or in fewer components. As this paper will demonstrate, SLS is making strong progress toward first launch, and represents a unique new capability for spaceflight, and an opportunity to reinvent space by developing out-of-the-box missions and mission designs unlike any flown before.

KENNEDY SPACE CENTER, FLA. -- In the Space Life Sciences (SLS) Lab, Jan Bauer, with Dynamac Corp., places samples of onion tissue in the elemental analyzer, which analyzes for carbon, hydrogen, nitrogen and sulfur. The 100,000 square-foot SLS houses labs for NASA’s ongoing research efforts, microbiology/microbial ecology studies and analytical chemistry labs. Also calling the new lab home are facilities for space flight-experiment and flight-hardware development, new plant growth chambers, and an Orbiter Environment Simulator that will be used to conduct ground control experiments in simulated flight conditions for space flight experiments. The SLS Lab, formerly known as the Space Experiment Research and Processing Laboratory or SERPL, provides space for NASA’s Life Sciences Services contractor Dynamac Corporation, Bionetics Corporation, and researchers from the University of Florida. NASA’s Office of Biological and Physical Research will use the facility for processing life sciences experiments that will be conducted on the International Space Station. The SLS Lab is the magnet facility for the International Space Research Park at KSC being developed in partnership with Florida Space Authority.

NASA Image and Video Library

2004-01-05

KENNEDY SPACE CENTER, FLA. -- In the Space Life Sciences (SLS) Lab, Jan Bauer, with Dynamac Corp., places samples of onion tissue in the elemental analyzer, which analyzes for carbon, hydrogen, nitrogen and sulfur. The 100,000 square-foot SLS houses labs for NASA’s ongoing research efforts, microbiology/microbial ecology studies and analytical chemistry labs. Also calling the new lab home are facilities for space flight-experiment and flight-hardware development, new plant growth chambers, and an Orbiter Environment Simulator that will be used to conduct ground control experiments in simulated flight conditions for space flight experiments. The SLS Lab, formerly known as the Space Experiment Research and Processing Laboratory or SERPL, provides space for NASA’s Life Sciences Services contractor Dynamac Corporation, Bionetics Corporation, and researchers from the University of Florida. NASA’s Office of Biological and Physical Research will use the facility for processing life sciences experiments that will be conducted on the International Space Station. The SLS Lab is the magnet facility for the International Space Research Park at KSC being developed in partnership with Florida Space Authority.

KENNEDY SPACE CENTER, FLA. -- In the Space Life Sciences (SLS) Lab, Jan Bauer, with Dynamac Corp., weighs samples of onion tissue for processing in the elemental analyzer behind it. The equipment analyzes for carbon, hydrogen, nitrogen and sulfur. The 100,000 square-foot SLS houses labs for NASA’s ongoing research efforts, microbiology/microbial ecology studies and analytical chemistry labs. Also calling the new lab home are facilities for space flight-experiment and flight-hardware development, new plant growth chambers, and an Orbiter Environment Simulator that will be used to conduct ground control experiments in simulated flight conditions for space flight experiments. The SLS Lab, formerly known as the Space Experiment Research and Processing Laboratory or SERPL, provides space for NASA’s Life Sciences Services contractor Dynamac Corporation, Bionetics Corporation, and researchers from the University of Florida. NASA’s Office of Biological and Physical Research will use the facility for processing life sciences experiments that will be conducted on the International Space Station. The SLS Lab is the magnet facility for the International Space Research Park at KSC being developed in partnership with Florida Space Authority.

NASA Image and Video Library

2004-01-05

KENNEDY SPACE CENTER, FLA. -- In the Space Life Sciences (SLS) Lab, Jan Bauer, with Dynamac Corp., weighs samples of onion tissue for processing in the elemental analyzer behind it. The equipment analyzes for carbon, hydrogen, nitrogen and sulfur. The 100,000 square-foot SLS houses labs for NASA’s ongoing research efforts, microbiology/microbial ecology studies and analytical chemistry labs. Also calling the new lab home are facilities for space flight-experiment and flight-hardware development, new plant growth chambers, and an Orbiter Environment Simulator that will be used to conduct ground control experiments in simulated flight conditions for space flight experiments. The SLS Lab, formerly known as the Space Experiment Research and Processing Laboratory or SERPL, provides space for NASA’s Life Sciences Services contractor Dynamac Corporation, Bionetics Corporation, and researchers from the University of Florida. NASA’s Office of Biological and Physical Research will use the facility for processing life sciences experiments that will be conducted on the International Space Station. The SLS Lab is the magnet facility for the International Space Research Park at KSC being developed in partnership with Florida Space Authority.

NASA's Space Launch System: An Evolving Capability for Exploration

NASA Technical Reports Server (NTRS)

Crumbly, Christopher M.; Creech, Stephen D.; Robinson,Kimberly F.

2016-01-01

Designed to meet the stringent requirements of human exploration missions into deep space and to Mars, NASA's Space Launch System (SLS) vehicle represents a unique new launch capability opening new opportunities for mission design. While SLS's super-heavy launch vehicle predecessor, the Saturn V, was used for only two types of missions - launching Apollo spacecraft to the moon and lofting the Skylab space station into Earth orbit - NASA is working to identify new ways to use SLS to enable new missions or mission profiles. In its initial Block 1 configuration, capable of launching 70 metric tons (t) to low Earth orbit (LEO), SLS is capable of not only propelling the Orion crew vehicle into cislunar space, but also delivering small satellites to deep space destinations. With a 5-meter (m) fairing consistent with contemporary Evolved Expendable Launch Vehicles (EELVs), the Block 1 configuration can also deliver science payloads to high-characteristic-energy (C3) trajectories to the outer solar system. With the addition of an upper stage, the Block 1B configuration of SLS will be able to deliver 105 t to LEO and enable more ambitious human missions into the proving ground of space. This configuration offers opportunities for launching co-manifested payloads with the Orion crew vehicle, and a new class of secondary payloads, larger than today's cubesats. The evolved configurations of SLS, including both Block 1B and the 130 t Block 2, also offer the capability to carry 8.4- or 10-m payload fairings, larger than any contemporary launch vehicle. With unmatched mass-lift capability, payload volume, and C3, SLS not only enables spacecraft or mission designs currently impossible with contemporary EELVs, it also offers enhancing benefits, such as reduced risk and operational costs associated with shorter transit time to destination and reduced risk and complexity associated with launching large systems either monolithically or in fewer components. As this paper will demonstrate, SLS represents a unique new capability for spaceflight, and an opportunity to reinvent space by developing out-of-the-box missions and mission designs unlike any flown before.

The collagen type I segment long spacing (SLS) and fibrillar forms: Formation by ATP and sulphonated diazo dyes.

PubMed

Harris, J Robin; Lewis, Richard J

2016-07-01

The collagen type I segment long spacing (SLS) crystallite is a well-ordered rod-like molecular aggregate, ∼300nm in length, which is produced in vitro under mildly acidic conditions (pH 2.5-3.5) in the presence of 1mM ATP. The formation of the SLS crystallite amplifies the inherent linear structural features of individual collagen heterotrimers, due to the punctate linear distribution and summation of the bulkier amino acid side chains along the length of individual collagen heterotrimers. This can be correlated structurally with the 67nm D-banded collagen fibril that is found in vivo, and formed in vitro. Although first described many years ago, the range of conditions required for ATP-induced SLS crystallite formation from acid-soluble collagen have not been explored extensively. Consequently, we have addressed biochemical parameters such as the ATP concentration, pH, speed of formation and stability so as to provide a more complete structural understanding of the SLS crystallite. Treatment of collagen type I with 1mM ATP at neutral and higher pH (6.0-9.0) also induced the formation of D-banded fibrils. Contrary to previous studies, we have shown that the polysulphonated diazo dyes Direct red (Sirius red) and Evans blue, but not Congo red and Methyl blue, can also induce the formation of SLS-like aggregates of collagen, but under markedly different ionic conditions to those employed in the presence of ATP. Specifically, pre-formed D-banded collagen fibrils, prepared in a higher than the usual physiological NaCl concentration (e.g. 500mM NaCl, 20mM Tris-HCl pH7.4 or x3 PBS), readily form SLS aggregates when treated with 0.1mM Direct red and Evans blue, but this did not occur at lower NaCl concentrations. These new data are discussed in relation to the anion (Cl(-)) and polyanion (phosphate and sulphonate) binding by the collagen heterotrimer and their likely role in collagen fibrillogenesis and SLS formation. Copyright © 2016 Elsevier Ltd. All rights reserved.

NASA's Space Launch System: A Heavy-Lift Platform for Entirely New Missions

NASA Technical Reports Server (NTRS)

Creech, Stephen A.

2012-01-01

The National Aeronautics and Space Administration s (NASA's) Space Launch System (SLS) will contribute a new capability for human space flight and scientific missions beyond low-Earth orbit. The SLS Program, managed at NASA s Marshall Space Fight Center, will develop the heavy-lift vehicle that will launch the Orion Multi-Purpose Crew Vehicle (MPCV), equipment, supplies, and major science missions. Orion will carry crews to space, provide emergency abort capability, sustain the crew during space travel, and provide safe reentry from deep-space return velocities. Supporting Orion s first autonomous flight to lunar orbit and back in 2017 and its first crewed flight in 2021, the SLS ultimately offers a flexible platform for both human and scientific exploration. The SLS plan leverages legacy infrastructure and hardware in NASA s inventory, as well as continues with advanced propulsion technologies now in development, to deliver an initial 70 metric ton (t) lift capability in 2017, evolving to a 130-t capability after 2021, using a block upgrade approach. This paper will give an overview of the SLS design and management approach against a backdrop of the missions it will support. It will detail the plan to deliver the initial SLS capability to the launch pad in the near term, as well as summarize the innovative approaches the SLS team is applying to deliver a safe, affordable, and sustainable long-range capability for entirely new missions opening a new realm of knowledge and a world of possibilities for multiple partners. Design reference missions that the SLS is being planned to support include asteroids, Lagrange Points, and Mars, among others. The Agency is developing its mission manifest in parallel with the development of a heavy-lift flagship that will dramatically increase total lift and volume capacity beyond current launch vehicle options, reduce trip times, and provide a robust platform for conducting new missions destined to rewrite textbooks with the information they deliver, while creating a framework for further collaboration among domestic and international partners, and potentially spurring economic expansion into new markets.

NASA's Space Launch System: Deep-Space Delivery for SmallSats

NASA Technical Reports Server (NTRS)

Robinson, Kimberly F.; Norris, George

2017-01-01

Designed for human exploration missions into deep space, NASA's Space Launch System (SLS) represents a new spaceflight infrastructure asset, enabling a wide variety of unique utilization opportunities. While primarily focused on launching the large systems needed for crewed spaceflight beyond Earth orbit, SLS also offers a game-changing capability for the deployment of small satellites to deep-space destinations, beginning with its first flight. Currently, SLS is making rapid progress toward readiness for its first launch in two years, using the initial configuration of the vehicle, which is capable of delivering more than 70 metric tons (t) to Low Earth Orbit (LEO). On its first flight, an uncrewed test of the Orion spacecraft into distant retrograde orbit around the moon, accompanying Orion on SLS will be 13 small-satellite secondary payloads, which will deploy in cislunar space. These secondary payloads will include not only NASA research, but also spacecraft from industry and international partners and academia. The payloads also represent a variety of disciplines including, but not limited to, studies of the moon, Earth, sun, and asteroids. The Space Launch System Program is working actively with the developers of the payloads toward vehicle integration. Following its first flight and potentially as early as its second, SLS will evolve into a more powerful configuration with a larger upper stage. This configuration will initially be able to deliver 105 t to LEO, and will continue to be upgraded to a performance of greater than 130 t to LEO. While the addition of the more powerful upper stage will mean a change to the secondary payload accommodations from those on the first launch, the SLS Program is already evaluating options for future secondary payload opportunities. Early discussions are also already underway for the use of SLS to launch spacecraft on interplanetary trajectories, which could open additional opportunities for small satellites. This presentation will include an overview of the SLS vehicle and its capabilities, including the current status of progress toward first launch. It will also explain the opportunities the vehicle offers for small satellites, including an overview of the CubeSat manifest for Exploration Mission-1 in 2018 and a discussion of future capabilities.

Selective laser sintering of calcium phosphate materials for orthopedic implants

NASA Astrophysics Data System (ADS)

Lee, Goonhee

Two technologies, Solid Freeform Fabrication (SFF) and bioceramics are combined in this work to prepare bone replacement implants with complex geometry. SFF has emerged as a crucial technique for rapid prototyping in the last decade. Selective Laser Sintering (SLS) is one of the established SFF manufacturing processes that can build three-dimensional objects directly from computer models without part-specific tooling or human intervention. Meanwhile, there have been great efforts to develop implantable materials that can assist in regeneration of bone defects and injuries. However, little attention has been focused in shaping bones from these materials. The main thrust of this research was to develop a process that can combine those two separate efforts. The specific objective of this research is to develop a process that can construct bone replacement material of complex geometry from synthetic calcium phosphate materials by using the SLS process. The achievement of this goal can have a significant impact on the quality of health care in the sense that complete custom-fit bone and tooth structures suitable for implantation can be prepared within 24--48 hours of receipt of geometric information obtained either from patient Computed Tomographic (CT) data, from Computer Aided Design (CAD) software or from other imaging systems such as Magnetic Resonance Imaging (MRI) and Holographic Laser Range Imaging (HLRI). In this research, two different processes have been developed. First is the SLS fabrication of porous bone implants. In this effort, systematic procedures have been established and calcium phosphate implants were successfully fabricated from various sources of geometric information. These efforts include material selection and preparation, SLS process parameter optimization, and development of post-processing techniques within the 48-hour time frame. Post-processing allows accurate control of geometry and of the chemistry of calcium phosphate, as well as control of micro and macro pore structure, to maximize bone healing and provide sufficient mechanical strength. It also permits the complete removal of the polymeric binders that are resided in the SLS process. In collaboration with the University of Texas Health Science Center at San Antonio and BioMedical Enterprises, Inc., porous implants based on anatomical geometry have been successfully implanted in rabbits and dogs. These histologic animal studies reveal excellent biocompatibility and show its great potential for commercial custom-fit implant manufacture. The second research effort involves fabrication of fully dense bone for application in dental restoration and load-bearing orthopedic functions. Calcium phosphate glass melts, proven to be biocompatible in the first effort, were cast into carbon molds. Processes were developed for preparing the molds. These carbon molds of anatomic shape can be prepared from either Computer Numerical Control (CNC) milling of slab stock or SLS processing of thermoset-coated graphite powder. The CNC milling method provides accurate dimension of the molds in a short period of time, however, the capable geometries are limited; generally two pieces of molds are required for complex shapes. The SLS method provides very complex shape green molds. However, they need to go through pyrolysis of thermoset binder to provide the high temperature capability reached at calcium phosphate melt temperatures (1100°C) and noticeable shrinkage was observed during pyrolysis. The cast glass was annealed to develop polycrystalline calcium phosphate. This process also exhibits great potential.

Sphingolipids role in the regulation of inflammatory response: From leukocyte biology to bacterial infection.

PubMed

Chiricozzi, Elena; Loberto, Nicoletta; Schiumarini, Domitilla; Samarani, Maura; Mancini, Giulia; Tamanini, Anna; Lippi, Giuseppe; Dechecchi, Maria Cristina; Bassi, Rosaria; Giussani, Paola; Aureli, Massimo

2018-03-01

Sphingolipids (SLs) are amphiphilic molecules mainly associated with the external leaflet of eukaryotic plasma membrane, and are structural membrane components with key signaling properties. Since the beginning of the last century, a large number of papers described the involvement of these molecules in several aspects of cell physiology and pathology. Several lines of evidence support the critical role of SLs in inflammatory diseases, by acting as anti- or pro-inflammatory mediators. They are involved in control of leukocyte activation and migration, and are recognized as essential players in host response to pathogenic infection. We propose here a critical overview of current knowledge on involvement of different classes of SLs in inflammation, focusing on the role of simple and complex SLs in pathogen-mediated inflammatory response. ©2018 Society for Leukocyte Biology.

Found in Translation: Applying Lessons from Model Systems to Strigolactone Signaling in Parasitic Plants.

PubMed

Lumba, Shelley; Subha, Asrinus; McCourt, Peter

2017-07-01

Strigolactones (SLs) are small molecules that act as endogenous hormones to regulate plant development as well as exogenous cues that help parasitic plants to infect their hosts. Given that parasitic plants are experimentally challenging systems, researchers are using two approaches to understand how they respond to host-derived SLs. The first involves extrapolating information on SLs from model genetic systems to dissect their roles in parasitic plants. The second uses chemicals to probe SL signaling directly in the parasite Striga hermonthica. These approaches indicate that parasitic plants have co-opted a family of α/β hydrolases to perceive SLs. The importance of this genetic and chemical information cannot be overstated since parasitic plant infestations are major obstacles to food security in the developing world. Copyright © 2017 Elsevier Ltd. All rights reserved.

Thermoreversible Gel Formulations Containing Sodium Lauryl Sulfate or n-Lauroylsarcosine as Potential Topical Microbicides against Sexually Transmitted Diseases

PubMed Central

Roy, Sylvie; Gourde, Pierrette; Piret, Jocelyne; Désormeaux, André; Lamontagne, Julie; Haineault, Caroline; Omar, Rabeea F.; Bergeron, Michel G.

2001-01-01

The microbicidal efficacies of two anionic surfactants, sodium lauryl sulfate (SLS) and n-lauroylsarcosine (LS), were evaluated in cultured cells and in a murine model of herpes simplex type 2 (HSV-2) intravaginal infection. In vitro studies showed that SLS and LS were potent inhibitors of the infectivity of HSV-2 strain 333. The concentrations of SLS which inhibit viral infectivity by 50% (50% inhibitory dose) and 90% (90% inhibitory dose) were 32.67 and 46.53 μM, respectively, whereas the corresponding values for LS were 141.76 and 225.30 μM. In addition, intravaginal pretreatment of mice with thermoreversible gel formulations containing 2.5% SLS or 2.5% LS prior to the inoculation of HSV-2 strain 333 completely prevented the development of genital herpetic lesions and the lethality associated with infection. Of prime interest, no infectious virus could be detected in mouse vaginal mucosa. Both formulations still provided significant protection when viral challenge was delayed until 1 h after pretreatment. Finally, intravaginal application of gel formulations containing 2.5% SLS or 2.5% LS once daily for 14 days to rabbits did not induce significant irritations to the genital mucosa, as demonstrated from macroscopic and histopathologic examinations. These results suggest that thermoreversible gel formulations containing SLS or LS could represent potent and safe topical microbicides for the prevention of HSV-2 and possibly other sexually transmitted pathogens, including human immunodeficiency virus. PMID:11353610

Skin penetration studies of Arnica preparations and of their sesquiterpene lactones.

PubMed

Wagner, Steffen; Suter, Andreas; Merfort, Irmgard

2004-10-01

Alcoholic preparations of Arnica montana are widely used for the topical treatment of various inflammatory diseases. Sesquiterpene lactones (SLs) are mainly responsible for their anti-inflammatory activity. Here we have studied the penetration kinetics of Arnica tinctures prepared from dried Arnica flowers originating from different chemotypes as well as of their respective dominating SLs, helenalin isobutyrate and 11alpha,13-dihydrohelenalin acetate. Some alcoholic preparations of fresh Arnica flowers and an Arnica fresh plant gel were also included in the study. We used the stripping method with adhesive tape and pig skin as a model and determined the quantity of SLs in the stripped layers of the stratum corneum (SC). Thus, we observed the penetration into and permeation through this uppermost part of the skin. Whereas isolated SLs permeate through the SC only in a very small amount, permeation of SLs was much higher when they were present in the tinctures. Furthermore, differences of permeation were observed between helenalin and dihydrohelenalin derivatives. Permeation through the SC could be determined for the tested Arnica preparations of fresh Arnica flowers with two preparations showing the best penetration behaviour of all the tested substances. Moreover, the effects of incubation time as well as of repeated applications were investigated with one preparation. Altogether, this study shows that a sufficient amount of SLs might permeate the skin barrier by using Arnica preparations to exert anti-inflammatory effects and that the topical use of plant preparations may be advantageous compared to the isolated compounds.

NASA's Space Launch System Progress Report

NASA Technical Reports Server (NTRS)

May, Todd A.; Singer, Joan A.; Cook, Jerry R.; Lyles, Garry M.; Beaman, David E.

2012-01-01

Exploration beyond Earth orbit will be an enduring legacy for future generations, as it provides a platform for science and exploration that will define new knowledge and redefine known boundaries. NASA s Space Launch System (SLS) Program, managed at the Marshall Space Flight Center, is responsible for designing and developing the first exploration-class rocket since the Apollo Program s Saturn V that sent Americans to the Moon in the 1960s and 1970s. The SLS offers a flexible design that may be configured for the Orion Multi-Purpose Crew Vehicle with associated life-support equipment and provisions for long journeys or may be outfitted with a payload fairing that will accommodate flagship science instruments and a variety of high-priority experiments. Building on legacy systems, facilities, and expertise, the SLS will have an initial lift capability of 70 tonnes (t) in 2017 and will be evolvable to 130 t after 2021. While commercial launch vehicle providers service the International Space Station market, this capability will surpass all vehicles, past and present, providing the means to do entirely new missions, such as human exploration of Mars. Building on the foundation laid by over 50 years of human and scientific space flight and on the lessons learned from the Apollo, Space Shuttle, and Constellation Programs the SLS team is delivering both technical trade studies and business case analyses to ensure that the SLS architecture will be safe, affordable, reliable, and sustainable. This panel will address the planning and progress being made by NASA s SLS Program.

Some ways of plants wastes utilization in bioregenerative life support systems

NASA Astrophysics Data System (ADS)

Kovaleva, N. P.; Tikhomirov, A. A.; Tirranen, L. S.; Ushakova, S. A.; Zolotukhin, I. G.; Anischenko, O. V.

In works on experimental modeling of bioregenerative life support systems BLSS carried out at Institute of Biophysics Russian Academy of Science Siberian Branch SB RAS the possibility of increase of a system closure degree under the condition of inedible plant biomass return into the organic matter turnover was demonstrated At the same time when radish inedible biomass was subjected to biological oxidation in soil-like substrate SLS after its drying then wheat straw was subjected to stepwise processing including mushrooms growing stage Mushrooms cultivation facilitated to lignin destruction and quicker straw decomposition On the other hand mushrooms growing required additional technological procedures leading to complication of a technological chain of straw processing The purpose of this work is to study the possibility of exclusion of mushrooms growing stage under straw pretreatment for its further use as an equivalent of radish edible biomass grown on SLS To solve the problem put by the radish cenosis in a conveyer regime was grown The conveyer included radish four ages with the conveyer step equal to 7 days The experiment consisted of two successive stages On the first stage radish was grown without straw addition into SLS control To return mineral elements into SLS the biomass grown was restored in SLS On the second stage inedible radish biomass and wheat straw were returned into SLS in the quantity equivalent to edible biomass The possibility of the method described was estimated according to plant productivity microbiological

Fabricating 3D printed orally disintegrating printlets using selective laser sintering.

PubMed

Fina, Fabrizio; Madla, Christine M; Goyanes, Alvaro; Zhang, Jiaxin; Gaisford, Simon; Basit, Abdul W

2018-04-25

Selective laser sintering (SLS) is a three-dimensional printing (3DP) technology employed to manufacture plastic, metallic or ceramic objects. The aim of this study was to demonstrate the feasibility of using SLS to fabricate novel solid dosage forms with accelerated drug release properties, and with a view to create orally disintegrating formulations. Two polymers (hydroxypropyl methylcellulose (HPMC E5) and vinylpyrrolidone-vinyl acetate copolymer (Kollidon ® VA 64)) were separately mixed with 5% paracetamol (used as a model drug) and 3% Candurin ® Gold Sheen colorant; the powder mixes were subjected to SLS printing, resulting in the manufacture of printlets (3DP tablets). Modulating the SLS printing parameters altered the release characteristics of the printlets, with faster laser scanning speeds accelerating drug release from the HPMC formulations. The same trend was observed for the Kollidon ® based printlets. At a laser scanning speed of 300 mm/s, the Kollidon ® printlets exhibited orally disintegrating characteristics by completely dispersing in <4 s in a small volume of water. X-ray micro-CT analysis of these printlets indicated a reduction in their density and an increase in open porosity, therefore, confirming the unique disintegration behaviour of these formulations. The work reported here is the first to demonstrate the feasibility of SLS 3DP to fabricate printlets with accelerated drug release and orally disintegrating properties. This investigation has confirmed that SLS is amenable to the pharmaceutical research of modern medicine manufacture. Copyright © 2018 Elsevier B.V. All rights reserved.

NASA's Space Launch System: Momentum Builds Towards First Launch

NASA Technical Reports Server (NTRS)

May, Todd; Lyles, Garry

2014-01-01

NASA's Space Launch System (SLS) is gaining momentum programmatically and technically toward the first launch of a new exploration-class heavy lift launch vehicle for international exploration and science initiatives. The SLS comprises an architecture that begins with a vehicle capable of launching 70 metric tons (t) into low Earth orbit. Its first mission will be the launch of the Orion Multi-Purpose Crew Vehicle (MPCV) on its first autonomous flight beyond the Moon and back. SLS will also launch the first Orion crewed flight in 2021. SLS can evolve to a 130-t lift capability and serve as a baseline for numerous robotic and human missions ranging from a Mars sample return to delivering the first astronauts to explore another planet. Managed by NASA's Marshall Space Flight Center, the SLS Program formally transitioned from the formulation phase to implementation with the successful completion of the rigorous Key Decision Point C review in 2014. At KDP-C, the Agency Planning Management Council determines the readiness of a program to go to the next life-cycle phase and makes technical, cost, and schedule commitments to its external stakeholders. As a result, the Agency authorized the Program to move forward to Critical Design Review, scheduled for 2015, and a launch readiness date of November 2018. Every SLS element is currently in testing or test preparations. The Program shipped its first flight hardware in 2014 in preparation for Orion's Exploration Flight Test-1 (EFT-1) launch on a Delta IV Heavy rocket in December, a significant first step toward human journeys into deep space. Accomplishments during 2014 included manufacture of Core Stage test articles and preparations for qualification testing the Solid Rocket Boosters and the RS-25 Core Stage engines. SLS was conceived with the goals of safety, affordability, and sustainability, while also providing unprecedented capability for human exploration and scientific discovery beyond Earth orbit. In an environment of economic challenges, the nationwide SLS team continues to meet ambitious budget and schedule targets through the studied use of hardware, infrastructure, and workforce investments the United States has already made in the last half century, while selectively using new technologies for design, manufacturing, and testing, as well as streamlined management approaches that have increased decision velocity and reduced associated costs. This paper will summarize recent SLS Program technical accomplishments, as well as the challenges and opportunities ahead for the most powerful and capable launch vehicle in history.

Laser Sintering Technology and Balling Phenomenon.

PubMed

Oyar, Perihan

2018-02-01

The aim of this review was to evaluate the balling phenomenon which occurs typically in Selective Laser Sintering (SLS). The balling phenomenon is a typical SLS defect, and observed in laser sintered powder, significantly reduces the quality of SLS, and hinders the further development of SLS Technology. Electronic database searches were performed using Google Scholar. The keywords "laser sintering, selective laser sintering, direct metal laser melting, and balling phenomenon" were searched in title/abstract of publications, limited to December 31, 2016. The inclusion criteria were SLS, balling phenomenon, some alloys (such as Cr-Co, iron, stainless steel, and Cu-based alloys) mechanical properties, microstructure and bond strength between metal-ceramic crown, laboratory studies, full text, and in English language. A total of 100 articles were found the initial search and yielded a total of 50 studies, 30 of which did not fulfill the inclusion criteria and were therefore excluded. In addition, 20 studies were found by screening the reference list of all included publications. Finally, 40 studies were selected for this review. The method in question is regulated by powder material characteristics and the conditions of laser processing. The procedure of formation, affecting factors, and the mechanism of the balling effect are very complex.

STS-40 Spacelab Life Sciences 1 (SLS-1): The first dedicated spacelab life sciences mission

NASA Technical Reports Server (NTRS)

1991-01-01

Successful exploration of space depends on the health and well-being of people who travel and work there. For this reason, the National Aeronautics and Space Administration (NASA) has dedicated several Space Shuttle missions to examine how living and working in space affects the human body. Spacelab Life Sciences 1 (SLS-1) is the first of these missions. The main purpose of the SLS-1 mission is to study the mechanisms, magnitudes, and time courses of certain physiological changes that occur during space flight and to investigate the consequences of the body's adaptation to microgravity and readjustment to gravity upon return to Earth. How does space flight influence the heart and circulatory system, metabolic processes, the muscles and bones, and the cells? If responses to weightlessness are undesirable, how can they be prevented or controlled? Will the human body maintain its physical and chemical equilibrium during months aboard a space station and years-long missions to Mars? When crews return to Earth, what can they expect to experience as their bodies readjust to Earth's gravity? With the SLS-1 experiments, NASA is addressing some of these questions. Various aspects of the SLS-1 are discussed.

Evaluation of soy-based surface active copolymers as surfactant ingredients in model shampoo formulations.

PubMed

Popadyuk, A; Kalita, H; Chisholm, B J; Voronov, A

2014-12-01

A new non-toxic soybean oil-based polymeric surfactant (SBPS) for personal-care products was developed and extensively characterized, including an evaluation of the polymeric surfactant performance in model shampoo formulations. To experimentally assure applicability of the soy-based macromolecules in shampoos, either in combination with common anionic surfactants (in this study, sodium lauryl sulfate, SLS) or as a single surface-active ingredient, the testing of SBPS physicochemical properties, performance and visual assessment of SBPS-based model shampoos was carried out. The results obtained, including foaming and cleaning ability of model formulations, were compared to those with only SLS as a surfactant as well as to SLS-free shampoos. Overall, the results show that the presence of SBPS improves cleaning, foaming, and conditioning of model formulations. SBPS-based formulations meet major requirements of multifunctional shampoos - mild detergency, foaming, good conditioning, and aesthetic appeal, which are comparable to commercially available shampoos. In addition, examination of SBPS/SLS mixtures in model shampoos showed that the presence of the SBPS enables the concentration of SLS to be significantly reduced without sacrificing shampoo performance. © 2014 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

Pulmonary function in microgravity

NASA Technical Reports Server (NTRS)

Guy, H. J.; Prisk, G. K.; West, J. B.

1992-01-01

We report the successful collection of a large quantity of human resting pulmonary function data on the SLS-1 mission. Preliminary analysis suggests that cardiac stroke volumes are high on orbit, and that an adaptive reduction takes at least several days, and in fact may still be in progress after 9 days on orbit. It also suggests that pulmonary capillary blood volumes are high, and remain high on orbit, but that the pulmonary interstitium is not significantly impacted. The data further suggest that the known large gravitational gradients of lung function have only a modest influence on single breath tests such as the SBN washout. They account for only approximately 25% of the phase III slope of nitrogen, on vital capacity SBN washouts. These gradients are only a moderate source of the cardiogenic oscillations seen in argon (bolus gas) and nitrogen (resident gas), on such tests. They may have a greater role in generating the normal CO2 oscillations, as here the phase relationship to argon and nitrogen reverses in microgravity, at least at mid exhalation in those subjects studied to date. Microgravity may become a useful tool in establishing the nature of the non-gravitational mechanisms that can now be seen to play such a large part in the generation of intra-breath gradients and oscillations of expired gas concentration. Analysis of microgravity multibreath nitrogen washouts, single breath washouts from more physiological pre-inspiratory volumes, both using our existing SLS-1 data, and data from the upcoming D-2 and SLS-2 missions, should be very fruitful in this regard.(ABSTRACT TRUNCATED AT 250 WORDS).

An Overview of the Launch Vehicle Blast Environments Development Efforts

NASA Technical Reports Server (NTRS)

Richardson, Erin; Bangham, Mike; Blackwood, James; Skinner, Troy; Hays, Michael; Jackson, Austin; Richman, Ben

2014-01-01

NASA has been funding an ongoing development program to characterize the explosive environments produced during a catastrophic launch vehicle accident. These studies and small-scale tests are focused on the near field environments that threaten the crew. The results indicate that these environments are unlikely to result in immediate destruction of the crew modules. The effort began as an independent assessment by NASA safety organizations, followed by the Ares program and NASA Engineering and Safety Center and now as a Space Launch Systems (SLS) focused effort. The development effort is using the test and accident data available from public or NASA sources as well as focused scaled tests that are examining the fundamental aspects of uncontained explosions of Hydrogen and air and Hydrogen and Oxygen. The primary risk to the crew appears to be the high-energy fragments and these are being characterized for the SLS. The development efforts will characterize the thermal environment of the explosions as well to ensure that the risk is well understood and to document the overall energy balance of an explosion. The effort is multi-path in that analytical, computational and focused testing is being used to develop the knowledge to understand potential SLS explosions. This is an ongoing program with plans that expand the development from fundamental testing at small-scale levels to large-scale tests that can be used to validate models for commercial programs. The ultimate goal is to develop a knowledge base that can be used by vehicle designers to maximize crew survival in an explosion.

Testing a new engine controller system for the RS-25

NASA Image and Video Library

2017-07-25

Engineers conduct the third in a series of RS-25 flight controller tests on July 25, 2017, for NASA’s Space Launch System (SLS) rocket. The more than 8 1/2 minute test on the A-1 Test Stand at NASA’s Stennis Space Center in Mississippi signaled another step toward launch of NASA’s new Space Launch System (SLS). The SLS rocket, powered by four RS-25 engines, along with the Orion spacecraft will take astronauts on a new era of exploration beyond Earth’s orbit into deep space.

Orion EM-1 Booster Preps - Aft Skirt Preps/Painting

NASA Image and Video Library

2016-10-28

Technicians with Orbital ATK, prime contractor for the Space Launch System (SLS) Booster, prepare the right hand aft skirt for NASA’s SLS rocket for primer and painting inside a support building at the Hangar AF facility at Cape Canaveral Air Force Station in Florida. The space shuttle-era aft skirt, was inspected and resurfaced and will be primed and painted for use on the right hand booster of the SLS rocket for Exploration Mission 1 (EM-1). NASA is preparing for EM-1, deep-space missions, and the journey to Mars.

Orion EM-1 Booster Preps - Aft Skirt Preps/Painting

NASA Image and Video Library

2016-10-28

Technicians with Orbital ATK, prime contractor for the Space Launch System (SLS) Booster, prepare a paint mixture for the right hand aft skirt for NASA’s SLS in a support building at the Hangar AF facility at Cape Canaveral Air Force Station in Florida. The space shuttle-era aft skirt, was inspected and resurfaced, and will be primed and painted for use on the right hand booster of the SLS rocket for Exploration Mission 1 (EM-1). NASA is preparing for EM-1, deep-space missions, and the Journey to Mars.

Additive Manufacturing: A Comparative Analysis of Dimensional Accuracy and Skin Texture Reproduction of Auricular Prostheses Replicas.

PubMed

Unkovskiy, Alexey; Spintzyk, Sebastian; Axmann, Detlef; Engel, Eva-Maria; Weber, Heiner; Huettig, Fabian

2017-11-10

The use of computer-aided design/computer-aided manufacturing (CAD/CAM) and additive manufacturing in maxillofacial prosthetics has been widely acknowledged. Rapid prototyping can be considered for manufacturing of auricular prostheses. Therefore, so-called prostheses replicas can be fabricated by digital means. The objective of this study was to identify a superior additive manufacturing method to fabricate auricular prosthesis replicas (APRs) within a digital workflow. Auricles of 23 healthy subjects (mean age of 37.8 years) were measured in vivo with respect to an anthropometrical protocol. Landmarks were volumized with fiducial balls for 3D scanning using a handheld structured light scanner. The 3D CAD dataset was postprocessed, and the same anthropometrical measurements were made in the CAD software with the digital lineal. Each CAD dataset was materialized using fused deposition modeling (FDM), selective laser sintering (SLS), and stereolithography (SL), constituting 53 APR samples. All distances between the landmarks were measured on the APRs. After the determination of the measurement error within the five data groups (in vivo, CAD, FDM, SLS, and SL), the mean values were compared using matched pairs method. To this, the in vivo and CAD dataset were set as references. Finally, the surface structure of the APRs was qualitatively evaluated with stereomicroscopy and profilometry to ascertain the level of skin detail reproduction. The anthropometrical approach showed drawbacks in measuring the protrusion of the ear's helix. The measurement error within all groups of measurements was calculated between 0.20 and 0.28 mm, implying a high reproducibility. The lowest mean differences of 53 produced APRs were found in FDM (0.43%) followed by SLS (0.54%) and SL (0.59%)--compared to in vivo, and again in FDM (0.20%) followed by SL (0.36%) and SLS (0.39%)--compared to CAD. None of these values exceed the threshold of clinical relevance (1.5%); however, the qualitative evaluation revealed slight shortcomings in skin reproduction for all methods: reproduction of skin details exceeding 0.192 mm in depth was feasible. FDM showed the superior dimensional accuracy and best skin surface reproduction. Moreover, digital acquisition and CAD postprocessing seem to play a more important role in the outcome than the additive manufacturing method used. © 2017 by the American College of Prosthodontists.

NASA Conducts First RS-25 Rocket Engine Test of 2015

NASA Image and Video Library

2015-01-09

From the Press Release: The new year is off to a hot start for NASA's Space Launch System (SLS). The engine that will drive America's next great rocket to deep space blazed through its first successful test Jan. 9 at the agency's Stennis Space Center near Bay St. Louis, Mississippi. The RS-25, formerly the space shuttle main engine, fired up for 500 seconds on the A-1 test stand at Stennis, providing NASA engineers critical data on the engine controller unit and inlet pressure conditions. This is the first hot fire of an RS-25 engine since the end of space shuttle main engine testing in 2009. Four RS-25 engines will power SLS on future missions, including to an asteroid and Mars. "We’ve made modifications to the RS-25 to meet SLS specifications and will analyze and test a variety of conditions during the hot fire series,” said Steve Wofford, manager of the SLS Liquid Engines Office at NASA's Marshall Space Flight Center in Huntsville, Alabama, where the SLS Program is managed. "The engines for SLS will encounter colder liquid oxygen temperatures than shuttle; greater inlet pressure due to the taller core stage liquid oxygen tank and higher vehicle acceleration; and more nozzle heating due to the four-engine configuration and their position in-plane with the SLS booster exhaust nozzles.” The engine controller unit, the "brain" of the engine, allows communication between the vehicle and the engine, relaying commands to the engine and transmitting data back to the vehicle. The controller also provides closed-loop management of the engine by regulating the thrust and fuel mixture ratio while monitoring the engine's health and status. The new controller will use updated hardware and software configured to operate with the new SLS avionics architecture. "This first hot-fire test of the RS-25 engine represents a significant effort on behalf of Stennis Space Center’s A-1 test team," said Ronald Rigney, RS-25 project manager at Stennis. "Our technicians and engineers have been working diligently to design, modify and activate an extremely complex and capable facility in support of RS-25 engine testing." Testing will resume in April after upgrades are completed on the high pressure industrial water system, which provides cool water for the test facility during a hot fire test. Eight tests, totaling 3,500 seconds, are planned for the current development engine. Another development engine later will undergo 10 tests, totaling 4,500 seconds. The second test series includes the first test of new flight controllers, known as green running. The first flight test of the SLS will feature a configuration for a 70-metric-ton (77-ton) lift capacity and carry an uncrewed Orion spacecraft beyond low-Earth orbit to test the performance of the integrated system. As the SLS is upgraded, it will provide an unprecedented lift capability of 130 metric tons (143 tons) to enable missions even farther into our solar system.

Kinematic predictors of single-leg squat performance: a comparison of experienced physiotherapists and student physiotherapists.

PubMed

Weeks, Benjamin K; Carty, Christopher P; Horan, Sean A

2012-10-25

The single-leg squat (SLS) is a common test used by clinicians for the musculoskeletal assessment of the lower limb. The aim of the current study was to reveal the kinematic parameters used by experienced and inexperienced clinicians to determine SLS performance and establish reliability of such assessment. Twenty-two healthy, young adults (23.8 ± 3.1 years) performed three SLSs on each leg whilst being videoed. Three-dimensional data for the hip and knee was recorded using a 10-camera optical motion analysis system (Vicon, Oxford, UK). SLS performance was rated from video data using a 10-point ordinal scale by experienced musculoskeletal physiotherapists and student physiotherapists. All ratings were undertaken a second time at least two weeks after the first by the same raters. Stepwise multiple regression analysis was performed to determine kinematic predictors of SLS performance scores and inter- and intra-rater reliability were determined using a two-way mixed model to generate intra-class correlation coefficients (ICC3,1) of consistency. One SLS per leg for each participant was used for analysis, providing 44 SLSs in total. Eight experienced physiotherapists and eight physiotherapy students agreed to rate each SLS. Variance in physiotherapist scores was predicted by peak knee flexion, knee medio-lateral displacement, and peak hip adduction (R2 = 0.64, p = 0.01), while variance in student scores was predicted only by peak knee flexion, and knee medio-lateral displacement (R2 = 0.57, p = 0.01). Inter-rater reliability was good for physiotherapists (ICC3,1 = 0.71) and students (ICC3,1 = 0.60), whilst intra-rater reliability was excellent for physiotherapists (ICC3,1 = 0.81) and good for students (ICC3,1 = 0.71). Physiotherapists and students are both capable of reliable assessment of SLS performance. Physiotherapist assessments, however, bear stronger relationships to lower limb kinematics and are more sensitive to hip joint motion than student assessments.

NASA's Space Launch System: An Evolving Capability for Exploration

NASA Technical Reports Server (NTRS)

Robinson, Kimberly F.; Hefner, Keith; Hitt, David

2015-01-01

Designed to enable human space exploration missions, including eventually landings on Mars, NASA's Space Launch System (SLS) represents a unique launch capability with a wide range of utilization opportunities, from delivering habitation systems into the "proving ground" of lunar-vicinity space to enabling high-energy transits through the outer solar system. Substantial progress has been made toward the first launch of the initial configuration of SLS, which will be able to deliver more than 70 metric tons of payload into low Earth orbit (LEO). Preparations are also underway to evolve the vehicle into more powerful configurations, culminating with the capability to deliver more than 130 metric tons to LEO. Even the initial configuration of SLS will be able to deliver greater mass to orbit than any contemporary launch vehicle, and the evolved configuration will have greater performance than the Saturn V rocket that enabled human landings on the moon. SLS will also be able to carry larger payload fairings than any contemporary launch vehicle, and will offer opportunities for co-manifested and secondary payloads. Because of its substantial mass-lift capability, SLS will also offer unrivaled departure energy, enabling mission profiles currently not possible. The basic capabilities of SLS have been driven by studies on the requirements of human deep-space exploration missions, and continue to be validated by maturing analysis of Mars mission options, including the Global Exploration Roadmap. Early collaboration with science teams planning future decadal-class missions have contributed to a greater understanding of the vehicle's potential range of utilization. As SLS draws closer to its first launch, the Program is maturing concepts for future capability upgrades, which could begin being available within a decade. These upgrades, from multiple unique payload accommodations to an upper stage providing more power for inspace propulsion, have ramifications for a variety of missions, from human exploration to robotic science.

NASA's Space Launch System: One Vehicle, Many Destinations

NASA Technical Reports Server (NTRS)

May, Todd A.; Creech, Stephen D.

2013-01-01

The National Aeronautics and Space Administration's (NASA's) Space Launch System (SLS) Program, managed at the Marshall Space Flight Center, is making progress toward delivering a new capability for exploration beyond Earth orbit. Developed with the goals of safety, affordability, and sustainability in mind, the SLS rocket will start its missions in 2017 with 10 percent more thrust than the Saturn V rocket that launched astronauts to the Moon 40 years ago. From there it will evolve into the most powerful launch vehicle ever flown, via an upgrade approach that will provide building blocks for future space exploration and development. The International Space Exploration Coordination Group, representing 12 of the world's space agencies, has created the Global Exploration Roadmap, which outlines paths toward a human landing on Mars, beginning with capability-demonstrating missions to the Moon or an asteroid. The Roadmap and corresponding NASA research outline the requirements for reference missions for all three destinations. This paper will explore the capability of SLS to meet those requirements and enable those missions. It will explain how the SLS Program is executing this development within flat budgetary guidelines by using existing engines assets and developing advanced technology based on heritage systems, from the initial 70 metric ton (t) lift capability through a block upgrade approach to an evolved 130-t capability. It will also detail the significant progress that has already been made toward its first launch in 2017. The SLS will offer a robust way to transport international crews and the air, water, food, and equipment they will need for extended trips to explore new frontiers. In addition, this paper will summarize the SLS rocket's capability to support science and robotic precursor missions to other worlds, or uniquely high-mass space facilities in Earth orbit. As this paper will explain, the SLS is making measurable progress toward becoming a global infrastructure asset for robotic and human scouts of all nations by providing the robust launch capability to deliver sustainable solutions for space exploration.

NASA Space Launch System Operations Strategy

NASA Technical Reports Server (NTRS)

Singer, Joan A.; Cook, Jerry R.; Singer, Christer E.

2012-01-01

The National Aeronautics and Space Administration s (NASA) Space Launch System (SLS) Program, managed at the Marshall Space Flight Center (MSFC), is charged with delivering a new capability for human and scientific exploration beyond Earth orbit (BEO). The SLS may also provide backup crew and cargo services to the International Space Station, where astronauts have been training for long-duration voyages to destinations such as asteroids and Mars. For context, the SLS will be larger than the Saturn V, providing 10 percent more thrust at liftoff in its initial 70 metric ton (t) configuration and 20 percent more in its evolved 130-t configuration. The SLS Program knows that affordability is the key to sustainability. This paper will provide an overview of its operations strategy, which includes initiatives to reduce both development and fixed costs by using existing hardware and infrastructure assets to meet a first launch by 2017 within the projected budget. It also has a long-range plan to keep the budget flat using competitively selected advanced technologies that offer appropriate return on investment. To arrive at the launch vehicle concept, the SLS Program conducted internal engineering and business studies that have been externally validated by industry and reviewed by independent assessment panels. A series of design reference missions has informed the SLS operations concept, including launching the Orion Multi-Purpose Crew Vehicle (MPCV) on an autonomous demonstration mission in a lunar flyby scenario in 2017, and the first flight of a crew on Orion for a lunar flyby in 2021. Additional concepts address the processing of very large payloads, using a series of modular fairings and adapters to flexibly configure the rocket for the mission. This paper will describe how the SLS, Orion, and Ground Systems Development and Operations (GSDO) programs are working together to create streamlined, affordable operations for sustainable exploration for decades to come.

Controllable growth of layered selenide and telluride heterostructures and superlattices using molecular beam epitaxy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vishwanath, Suresh; Liu, Xinyu; Rouvimov, Sergei

2016-01-06

Layered materials are an actively pursued area of research for realizing highly scaled technologies involving both traditional device structures as well as new physics. Lately, non-equilibrium growth of 2D materials using molecular beam epitaxy (MBE) is gathering traction in the scientific community and here we aim to highlight one of its strengths, growth of abrupt heterostructures, and superlattices (SLs). In this work we present several of the firsts: first growth of MoTe 2 by MBE, MoSe 2 on Bi 2Se 3 SLs, transition metal dichalcogenide (TMD) SLs, and lateral junction between a quintuple atomic layer of Bi 2Te 3 andmore » a triple atomic layer of MoTe 2. In conclusion, reflected high electron energy diffraction oscillations presented during the growth of TMD SLs strengthen our claim that ultrathin heterostructures with monolayer layer control is within reach.« less

Combined mismatch repair and POLE/POLD1 defects explain unresolved suspected Lynch syndrome cancers

PubMed Central

Jansen, Anne ML; van Wezel, Tom; van den Akker, Brendy EWM; Ventayol Garcia, Marina; Ruano, Dina; Tops, Carli MJ; Wagner, Anja; Letteboer, Tom GW; Gómez-García, Encarna B; Devilee, Peter; Wijnen, Juul T; Hes, Frederik J; Morreau, Hans

2016-01-01

Many suspected Lynch Syndrome (sLS) patients who lack mismatch repair (MMR) germline gene variants and MLH1 or MSH2 hypermethylation are currently explained by somatic MMR gene variants or, occasionally, by germline POLE variants. To further investigate unexplained sLS patients, we analyzed leukocyte and tumor DNA of 62 sLS patients using gene panel sequencing including the POLE, POLD1 and MMR genes. Forty tumors showed either one, two or more somatic MMR variants predicted to affect function. Nine sLS tumors showed a likely ultramutated phenotype and were found to carry germline (n=2) or somatic variants (n=7) in the POLE/POLD1 exonuclease domain (EDM). Six of these POLE/POLD1-EDM mutated tumors also carried somatic MMR variants. Our findings suggest that faulty proofreading may result in loss of MMR and thereby in microsatellite instability. PMID:26648449

Control of acid drainage from fresh coal refuse: food preservatives as economical alternatives to detergents

DOE Office of Scientific and Technical Information (OSTI.GOV)

Onysko, S.J.; Erickson, P.M.; Kleinmann, R.L.P.

Water soluble detergents such as sodium lauryl sulfate (SLS), which can sorb to pyritic materials, have been successfully used by the mining industry for acid drainage prevention in coal refuse. Detergent control of acid drainage from refuse may be uneconomical, however, at sites where extensive rainfall or groundwater movement results in rapid SLS washout. In this study, the performance of two alternative acid control chemicals, sodium benzoate and potassium sorbate, was compared with the performance of SLS in pilot-scale experiments with extensively leached, fresh coal refuse. Chemical cost information is presented that indicates low benzoate and sorbate doses were moremore » economical than comparable SLS doses under the experimental conditions of the study. The unique environmental compatibility of benzoate and sorbate, which are used in food and beverages in concentrations greater than those reported in this study for acid drainage suppression, is also discussed.« less

NASA Marches on with Test of RS-25 Engine for New Space Launch System

NASA Image and Video Library

2016-07-29

NASA engineers conducted a successful developmental test of RS-25 rocket engine No. 0528 July 29, 2016, to collect critical performance data for the most powerful rocket in the world – the Space Launch System (SLS). The engine roared to life for a full 650-second test on the A-1 Test Stand at NASA’s Stennis Space Center, near Bay St. Louis, Mississippi, marking another step forward in development of the SLS, which will launch humans deeper into space than ever before, including on the journey to Mars. Four RS-25 engines, joined with a pair of solid rocket boosters, will power the SLS core stage at launch. The RS-25 engines used on the first four SLS flights are former space shuttle main engines, modified to operate at a higher performance level and with a new engine controller, which allows communication between the vehicle and engine.

VAB Platform K(2) Lift & Install into Highbay 3

NASA Image and Video Library

2016-03-07

Preparations are underway to lift the second half of the K-level work platforms for NASA’s Space Launch System (SLS) rocket up from High Bay 4 inside the Vehicle Assembly Building at NASA's Kennedy Space Center in Florida. The platform will be lifted up and over the transfer aisle and then lowered into High Bay 3 for installation. It will be secured about 86 feet above the VAB floor, on tower E of the high bay. The K work platforms will provide access to the SLS core stage and solid rocket boosters during processing and stacking operations on the mobile launcher. The Ground Systems Development and Operations Program is overseeing upgrades and modifications to High Bay 3 to support processing of the SLS and Orion spacecraft. A total of 10 levels of new platforms, 20 platform halves altogether, will surround the SLS rocket and Orion spacecraft.

VAB Platform K(2) Lift & Install into Highbay 3

NASA Image and Video Library

2016-03-07

A 250-ton crane is used to lift the second half of the K-level work platforms for NASA’s Space Launch System (SLS) rocket high above the transfer aisle inside the Vehicle Assembly Building at NASA's Kennedy Space Center in Florida. The platform is being lifted up for transfer into High Bay 3 for installation. The platform will be secured about 86 feet above the VAB floor, on tower E of the high bay. The K work platforms will provide access to the SLS core stage and solid rocket boosters during processing and stacking operations on the mobile launcher. The Ground Systems Development and Operations Program is overseeing upgrades and modifications to High Bay 3 to support processing of the SLS and Orion spacecraft. A total of 10 levels of new platforms, 20 platform halves altogether, will surround the SLS rocket and Orion spacecraft.

VAB Platform K(2) Lift & Install into Highbay 3

NASA Image and Video Library

2016-03-07

A 250-ton crane is used to lift the second half of the K-level work platforms for NASA’s Space Launch System (SLS) rocket up from High Bay 4 inside the Vehicle Assembly Building at NASA's Kennedy Space Center in Florida. The platform will be lifted up and over the transfer aisle and then lowered into High Bay 3 for installation. It will be secured about 86 feet above the VAB floor, on tower E of the high bay. The K work platforms will provide access to the SLS core stage and solid rocket boosters during processing and stacking operations on the mobile launcher. The Ground Systems Development and Operations Program is overseeing upgrades and modifications to High Bay 3 to support processing of the SLS and Orion spacecraft. A total of 10 levels of new platforms, 20 platform halves altogether, will surround the SLS rocket and Orion spacecraft.

VAB Platform K(2) Lift & Install into Highbay 3

NASA Image and Video Library

2016-03-07

A 250-ton crane is used to lift the second half of the K-level work platforms for NASA’s Space Launch System (SLS) rocket up from High Bay 4 inside the Vehicle Assembly Building at NASA's Kennedy Space Center in Florida. The platform is being lifted up and over the transfer aisle and will be lowered into High Bay 3 for installation. It will be secured about 86 feet above the VAB floor, on tower E of the high bay. The K work platforms will provide access to the SLS core stage and solid rocket boosters during processing and stacking operations on the mobile launcher. The Ground Systems Development and Operations Program is overseeing upgrades and modifications to High Bay 3 to support processing of the SLS and Orion spacecraft. A total of 10 levels of new platforms, 20 platform halves altogether, will surround the SLS rocket and Orion spacecraft.

Building Aerodynamic Databases for the SLS Design Process

NASA Technical Reports Server (NTRS)

Rogers, Stuart; Dalle, Derek J.; Lee, Henry; Meeroff, Jamie; Onufer, Jeffrey; Chan, William; Pulliam, Thomas

2017-01-01

NASA's new Space Launch System (SLS) will be the first rocket since the Saturn V (1967-1973) to carry astronauts beyond low earth orbit-and will carry 10% more payload than Saturn V and three times the payload of the space shuttle. The SLS configuration consists of a center core and two solid rocket boosters that separate from the core as their fuel is exhausted two minutes after lift-off. During these first two minutes of flight, the vehicle powers its way through strong shock waves as it accelerates past the speed of sound, then pushes beyond strong aerodynamic loads at the maximum dynamic pressure, and is ultimately enveloped by gaseous plumes from the booster-separation motors. The SLS program relies on computational fluid dynamic (CFD) simulations to provide much of the data needed to build aerodynamic databases describing the structural load distribution, surface pressures, and aerodynamic forces on the vehicle.

Teaching communication and supporting autonomy with a team-based operative simulator.

PubMed

Cook, Mackenzie R; Deal, Shanley B; Scott, Jessica M; Moren, Alexis M; Kiraly, Laszlo N

2016-09-01

Changing residency structure emphasizes the need for formal instruction on team leadership and intraoperative teaching skills. A high fidelity, multi-learner surgical simulation may offer opportunities for senior learners (SLs) to learn these skills while teaching technical skills to junior learners (JLs). We designed and optimized a low-cost inguinal hernia model that paired JLs and SLs as an operative team. This was tested in 3 pilot simulations. Participants' feedback was analyzed using qualitative methods. JL feedback to SLs included the themes "guiding and instructing" and "allowing autonomy." Senior Learner feedback to JLs focused on "mechanics," "knowledge," and "perspective/flow." Both groups focused on "communication" and "professionalism." A multi-learner simulation can successfully meet the technical learning needs of JLs and the teaching and communication learning needs of SLs. This model of resident-driven simulation may illustrate future opportunities for operative simulation. Copyright © 2016 Elsevier Inc. All rights reserved.

SLS-1 flight experiments preliminary significant results

NASA Technical Reports Server (NTRS)

1992-01-01

Spacelab Life Sciences-1 (SLS-1) is the first of a series of dedicated life sciences Spacelab missions designed to investigate the mechanisms involved in the physiological adaptation to weightlessness and the subsequent readaptation to 1 gravity (1 G). Hypotheses generated from the physiological effects observed during earlier missions led to the formulation of several integrated experiments to determine the underlying mechanisms responsible for the observed phenomena. The 18 experiments selected for flight on SLS-1 investigated the cardiovascular, cardiopulmonary, regulatory physiology, musculoskeletal, and neuroscience disciplines in both human and rodent subjects. The SLS-1 preliminary results gave insight to the mechanisms involved in the adaptation to the microgravity environment and readaptation when returning to Earth. The experimental results will be used to promote health and safety for future long duration space flights and, as in the past, will be applied to many biomedical problems encountered here on Earth.

Multiple continuous coverage of the earth based on multi-satellite systems with linear structure

NASA Astrophysics Data System (ADS)

Saulskiy, V. K.

2009-04-01

A new and wider definition is given to multi-satellite systems with linear structure (SLS), and efficiency of their application to multiple continuous coverage of the Earth is substantiated. Owing to this widening, SLS have incorporated already well-recognized “polar systems” by L. Rider and W.S. Adams, “kinematically regular systems” by G.V. Mozhaev, and “delta-systems” by J.G. Walker, as well as “near-polar systems” by Yu.P. Ulybyshev, and some other satellite constellations unknown before. A universal method of SLS optimization is presented, valid for any values of coverage multiplicity and the number of satellites in a system. The method uses the criterion of minimum radius of a circle seen from a satellite on the surface of the globe. Among the best SLS found in this way there are both systems representing the well-known classes mentioned above and new orbit constellations of satellites.

Efficient production of sophorolipids by Starmerella bombicola using a corncob hydrolysate medium.

PubMed

Konishi, Masaaki; Yoshida, Yuka; Horiuchi, Jun-ichi

2015-03-01

Sophorolipids (SLs) are amphiphilic compounds produced from a variety of saccharides and vegetable oils by the yeast Starmerella bombicola and related strains, and they have commercial uses as detergents. In the present study, SL production was investigated using a corncob hydrolysate (CCH) medium derived from lignocellulosic feedstocks as a source of hydrophilic carbon substrates. Excess sulfuric acid concentrations during pretreatment of the corncobs increased the furfural concentrations and turned the CCH dark brown. The optimal sulfuric acid concentration was 1% (w/v), and the treated CCH, containing 45 g/l glucose, allowed the production of 33.7 g/l of SLs following 4 days of cultivation. Additional autoclaving (121°C, 20 min) inhibited SL production and cell growth by 36% and 40%, respectively. Ammonium nitrate (0.1 g-N/l) restored SL production to the autoclaved CCH. Finally, a cost-effective SL production of 49.2 g/l, with a volumetric productivity of 12.3 g/l/day, was achieved using CCH medium during batch cultivation in a jar fermentor. Copyright © 2014 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Effect of sodium lauryl sulfate-fumaric Acid coupled addition on the in vitro rumen fermentation with special regard to methanogenesis.

PubMed

Abdl-Rahman, M A; Sawiress, F A R; Abd El-Aty, A M

2010-01-01

The aim of the current study was to evaluate the effect of sodium lauryl sulfate-fumaric acid coupled addition on in vitro methangenesis and rumen fermentation. Evaluation was carried out using in vitro gas production technique. Ruminal contents were collected from five steers immediately after slaughtering and used for preparation of inoculums of mixed rumen microorganisms. Rumen fluid was then mixed with the basal diet of steers and used to generate four treatments, negative control (no additives), sodium lauryl sulfate (SLS) treated, fumaric acid treated, and SLS-fumaric acid coupled addition treated. The results revealed that, relative to control, efficiency in reduction of methanogenesis was as follows: coupled addition > SLS-addition > fumaric acid addition. Both SLS-addition and SLS-fumaric acid coupled addition demonstrated a decremental effect on ammonia nitrogen (NH(3)-N), total short chain volatile fatty acids (SCVFAs) concentrations and the amount of substrate degraded, and an increment effect on microbial mass and microbial yield (Y(ATP)). Nevertheless, fumaric acid did not alter any of the previously mentioned parameters but induced a decremental effect on NH(3)-N. Furthermore, both fumaric acid and SLS-fumaric acid coupled addition increased propionate at the expense of acetate and butyrate, while, defaunation increased acetate at the expense of propionate and butyrate. The pH value was decreased by all treatments relative to control, while, cellulase activity did not differ by different treatments. The current study can be promising strategies for suppressing ruminal methane emissions and improving ruminants feed efficiency.

Effect of Sodium Lauryl Sulfate-Fumaric Acid Coupled Addition on the In Vitro Rumen Fermentation with Special Regard to Methanogenesis

PubMed Central

Abdl-Rahman, M. A.; Sawiress, F. A. R.; Abd El-Aty, A. M.

2010-01-01

The aim of the current study was to evaluate the effect of sodium lauryl sulfate-fumaric acid coupled addition on in vitro methangenesis and rumen fermentation. Evaluation was carried out using in vitro gas production technique. Ruminal contents were collected from five steers immediately after slaughtering and used for preparation of inoculums of mixed rumen microorganisms. Rumen fluid was then mixed with the basal diet of steers and used to generate four treatments, negative control (no additives), sodium lauryl sulfate (SLS) treated, fumaric acid treated, and SLS-fumaric acid coupled addition treated. The results revealed that, relative to control, efficiency in reduction of methanogenesis was as follows: coupled addition > SLS-addition > fumaric acid addition. Both SLS-addition and SLS-fumaric acid coupled addition demonstrated a decremental effect on ammonia nitrogen (NH3–N), total short chain volatile fatty acids (SCVFAs) concentrations and the amount of substrate degraded, and an increment effect on microbial mass and microbial yield (YATP). Nevertheless, fumaric acid did not alter any of the previously mentioned parameters but induced a decremental effect on NH3–N. Furthermore, both fumaric acid and SLS-fumaric acid coupled addition increased propionate at the expense of acetate and butyrate, while, defaunation increased acetate at the expense of propionate and butyrate. The pH value was decreased by all treatments relative to control, while, cellulase activity did not differ by different treatments. The current study can be promising strategies for suppressing ruminal methane emissions and improving ruminants feed efficiency. PMID:20445794

A conceptual configuration of the lunar base bioregenerative life support system including soil-like substrate for growing plants

NASA Astrophysics Data System (ADS)

Liu, H.; Yu, C. Y.; Manukovsky, N. S.; Kovalev, V. S.; Gurevich, Yu L.; Wang, J.

2008-09-01

The paper presents a conceptual configuration of the lunar base bioregenerative life support system (LBLSS), including soil-like substrate (SLS) for growing plants. SLS makes it possible to combine the processes of plant growth and the utilization of plant waste. Plants are to be grown on SLS on the basis of 20 kg of dry SLS mass or 100 kg of wet SLS mass per square meter. The substrate is to be delivered to the base ready-made as part of the plant growth subsystem. Food for the crew was provided by prestored stock 24% and by plant growing system 76%. Total dry weight of the food is 631 g per day (2800 kcal/day) for one crew member (CM). The list of candidate plants to be grown under lunar BLSS conditions included 14 species: wheat, rice, soybean, peanuts, sweet pepper, carrots, tomatoes, coriander, cole, lettuce, radish, squash, onion and garlic. From the prestored stock the crew consumed canned fish, iodinated salt, sugar, beef sauce and seafood sauce. Our calculations show that to provide one CM with plant food requires the area of 47.5 m 2. The balance of substance is achieved by the removal dehydrated urine 59 g, feces 31 g, food waste 50 g, SLS 134 g, and also waters 86 g from system and introduction food 236 g, liquid potassium soap 4 g and mineral salts 120 g into system daily. To reduce system setup time the first plants could be sowed and germinated to a certain age on the Earth.

A comparison of systemwide and hospital-specific performance measurement tools.

PubMed

Yap, Clarence; Siu, Emily; Baker, G Ross; Brown, Adalsteinn D

2005-01-01

Balanced scorecards are being implemented at the system and organizational levels to help managers link their organizational strategies with performance data to better manage their healthcare systems. Prior to this study, hospitals in Ontario, Canada, received two editions of the system-level scorecard (SLS)--a framework, based on the original balanced scorecard, that includes four quadrants: system integration and management innovation (learning and growth), clinical utilization and outcomes (internal processes), patient satisfaction (customer), and financial performance and condition (financial). This study examines the uptake of the SLS framework and indicators into institution-specific scorecards for 22 acute care institutions and 2 non-acute-care institutions. This study found that larger (teaching and community) hospitals were significantly more likely to use the SLS framework to report performance data than did small hospitals (p < 0.0049 and 0.0507) and that teaching hospitals used the framework significantly more than community hospitals did (p < 0.0529). The majority of hospitals in this study used at least one indicator from the SLS in their own scorecards. However, all hospitals in the study incorporated indicators that required data collection and analysis beyond the SLS framework. The study findings suggest that SLS may assist hospitals in developing institution-specific scorecards for hospital management and that the balanced scorecard model can be modified to meet the needs of a variety of hospitals. Based on the insight from this study and other activities that explore top priorities for hospital management, the issues related to efficiency and human resources should be further examined using SLSs.

The Initial Comparison Study of Sodium Lignosulfonate, Sodium Dodecyl Benzene Sulfonate, and Sodium p-Toluene Sulfonate Surfactant for Enhanced Oil Recovery

NASA Astrophysics Data System (ADS)

Khoirul Anas, Argo; Iman Prakoso, Nurcahyo; Sasvita, Dilla

2018-04-01

Surfactant (surface active agent) exhibit numerous interesting properties that enable their use as additional component in mobilising of residual oil from capillary pore after secondary recovery process using gas injection and water flooding. In this study, Sodium Lignosulfonate (SLS) surfactant was successfully synthesized by applying batch method using lignin from oil palm empty fruit bunches as precursor. Furthermore, its performance in reducing interfacial tension of crude oil and formation water colloidal system was compared with commercial available surfactant including Sodium Dodecyl Benzene Sulfonate (SDBS) and Sodium p-Toluene Sulfonate (SpTS). The synthesized SLS surfactant was characterized by using Fourier Transform Infrared (FTIR) spectroscopy. Meanwhile, its performance in reducing interfacial tension of crude oil and formation water colloidal system was analyzed by using compatibility test, phase behaviour analysis, and interfacial tension (IFT) measurement. The compatibility test shows that SLS, SDBS, and SpTS surfactants were compatible with formation water. In addition, the phase behaviour analysis shows that SLS surfactant was better than SpTS surfactant, while SDBS surfactant generates the highest performance proved by the best microemulsion formation resulted by SDBS. Furthermore, the optimum concentration of SLS, SDBS, and SpTS surfactants in reducing the interfacial tension of crude oil and formation water was 1.0%. The IFT measurement indicates that the performance of SLS with the value of 1.67 mN/m was also better than SpTS surfactant with the value of 3.59 mN/m. Meanwhile, SDBS surfactant shows the best performance with the IFT value of 0.47 mN/m.

Space Launch System Implementation of Adaptive Augmenting Control

NASA Technical Reports Server (NTRS)

Wall, John H.; Orr, Jeb S.; VanZwieten, Tannen S.

2014-01-01

Given the complex structural dynamics, challenging ascent performance requirements, and rigorous flight certification constraints owing to its manned capability, the NASA Space Launch System (SLS) launch vehicle requires a proven thrust vector control algorithm design with highly optimized parameters to provide stable and high-performance flight. On its development path to Preliminary Design Review (PDR), the SLS flight control system has been challenged by significant vehicle flexibility, aerodynamics, and sloshing propellant. While the design has been able to meet all robust stability criteria, it has done so with little excess margin. Through significant development work, an Adaptive Augmenting Control (AAC) algorithm has been shown to extend the envelope of failures and flight anomalies the SLS control system can accommodate while maintaining a direct link to flight control stability criteria such as classical gain and phase margin. In this paper, the work performed to mature the AAC algorithm as a baseline component of the SLS flight control system is presented. The progress to date has brought the algorithm design to the PDR level of maturity. The algorithm has been extended to augment the full SLS digital 3-axis autopilot, including existing load-relief elements, and the necessary steps for integration with the production flight software prototype have been implemented. Several updates which have been made to the adaptive algorithm to increase its performance, decrease its sensitivity to expected external commands, and safeguard against limitations in the digital implementation are discussed with illustrating results. Monte Carlo simulations and selected stressing case results are also shown to demonstrate the algorithm's ability to increase the robustness of the integrated SLS flight control system.

SLS Intertank Test Article, ITA, is attached to crosshead of loa

NASA Image and Video Library

2018-04-04

SLS Intertank Test Article, ITA, is attached to crosshead of load test Annex, Bldg. 4619, and removed from bed of KMAG transporter. ITA is slowly raised from bed of KMAG transporter and KMAG is removed.

Sodium Lauryl Sulfate Competitively Interacts with HPMC-AS and Consequently Reduces Oral Bioavailability of Posaconazole/HPMC-AS Amorphous Solid Dispersion.

PubMed

Chen, Yuejie; Wang, Shujing; Wang, Shan; Liu, Chengyu; Su, Ching; Hageman, Michael; Hussain, Munir; Haskell, Roy; Stefanski, Kevin; Qian, Feng

2016-08-01

Sodium lauryl sulfate (SLS), as an effective surfactant, is often used as a solubilizer and/or wetting agent in various dosage forms for the purpose of improving the solubility and dissolution of lipophilic, poorly water-soluble drugs. This study aims to understand the impact of SLS on the solution behavior and bioavailability of hypromellose acetate succinate (HPMC-AS)-based posaconazole (PSZ) ASDs, and to identify the underlying mechanisms governing the optimal oral bioavailability of ASDs when surfactants such as SLS are used in combination. Fluorescence spectroscopy and optical microscopy showed that "oil-out" or "liquid-liquid phase separation (LLPS)" occurred in the supersaturated PSZ solution once drug concentration surpassed ∼12 μg/mL, which caused the formation of drug-rich oily droplets with initial size of ∼300-400 nm. Although FT-IR study demonstrated the existence of specific interactions between PSZ and HPMC-AS in the solid state, predissolved HPMC-AS was unable to delay LLPS of the supersaturated PSZ solution and PSZ-rich amorphous precipitates with ∼16-18% HPMC-AS were formed within 10 min. The coprecipitated HPMC-AS was found to be able to significantly delay the crystallization of PSZ in the PSZ-rich amorphous phase from less than 10 min to more than 4 h, yet coexistent SLS was able to negate this crystallization inhibition effect of HPMC-AS in the PSZ-rich amorphous precipitates and cause fast PSZ crystallization within 30 min. 2D-NOESY and the CMC/CAC results demonstrated that SLS could assemble around HPMC-AS and competitively interact with HPMC-AS in the solution, thus prevent HPMC-AS from acting as an effective crystallization inhibitor. In a crossover dog PK study, this finding was found to be correlating well with the in vivo bioavailability of PSZ ASDs formulated with or without SLS. The SLS containing PSZ ASD formulation demonstrated an in vivo bioavailability ∼30% of that without SLS, despite the apparently better in vitro dissolution, which only compared the dissolved drug in solution, a small fraction of the total PSZ dose. We conclude that the bioavailability of ASDs is highly dependent on the molecular interactions between drug, surfactant, and polymer, not only in the solution phase but also in the drug-rich "oily" phase caused by supersaturation.

Space Launch System, Core Stage, Structural Test Design and Implementation

NASA Technical Reports Server (NTRS)

Shaughnessy, Ray

2017-01-01

As part of the National Aeronautics and Space Administration's (NASA) Space Launch System (SLS) Program, engineers at NASA's Marshall Space Flight Center (MSFC) in Huntsville, Alabama are working to design, develop and implement the SLS Core Stage structural testing. The SLS will have the capability to return humans to the Moon and beyond and its first launch is scheduled for December of 2017. The SLS Core Stage consist of five major elements; Forward Skirt, Liquid Oxygen (LOX) tank, Intertank (IT), Liquid Hydrogen (LH2) tank and the Engine Section (ES). Structural Test Articles (STA) for each of these elements are being designed and produced by Boeing at Michoud Assembly Facility located in New Orleans, La. The structural test for the Core Stage STAs (LH2, LOX, IT and ES) are to be conducted by the MSFC Test Laboratory. Additionally, the MSFC Test Laboratory manages the Structural Test Equipment (STE) design and development to support the STAs. It was decided early (April 2012) in the project life that the LH2 and LOX tank STAs would require new test stands and the Engine Section and Intertank would be tested in existing facilities. This decision impacted schedules immediately because the new facilities would require Construction of Facilities (C of F) funds that require congressional approval and long lead times. The Engine Section and Intertank structural test are to be conducted in existing facilities which will limit lead times required to support the first launch of SLS. With a SLS launch date of December, 2017 Boeing had a need date for testing to be complete by September of 2017 to support flight certification requirements. The test facilities were required to be ready by October of 2016 to support test article delivery. The race was on to get the stands ready before Test Article delivery and meet the test complete date of September 2017. This paper documents the past and current design and development phases and the supporting processes, tools, and methodology for supporting the SLS Core Stage STA test stands and related STE. The paper will address key requirements, system development activities and project challenges. Additionally, the interrelationships as well as interdependencies within the SLS project will be discussed.

The SLS Stages Intertank Structural Test Assembly (STA) arrives at MSFC.

NASA Image and Video Library

2018-03-06

The SLS Stages Intertank Structural Test Assembly (STA) is rolling off the NASA Pegasus Barge at the MSFC Dock enroute to the MSFC 4619 Load Test Annex test facility for qualification testing. STA emerges from Barge Pegasus.

Synthesis of sodium lauryl sulphate (SLS)-modified activated carbon from risk husk for waste lead (Pb) removal

NASA Astrophysics Data System (ADS)

Al-Latief, D. N.; Arnelli, Astuti, Y.

2015-12-01

Surfactant-modified active carbon (SMAC) has been successfully synthesized from waste rice husk using a series of treatments i.e. carbonization, activation with H3PO4 and surface modification using sodium lauryl sulfate (SLS). The synthesized SMAC was characterized using SEM-EDX and FTIR. The adsorption results show that the SMAC synthesized using H3PO4 treatment for 8 hours followed with SLS treatment for 5 hours had efficiency and capacity of the waste lead removal of 99.965% and 0.499825 mg.g-1, respectively.

NASA’s Stennis Space Center Conducts RS-25 Engine Test

NASA Image and Video Library

2017-03-24

On March 23, NASA conducted a test of an RS-25 engine at the agency’s Stennis Space Center in Bay St. Louis, Mississippi. Four RS-25’s will help power NASA’s Space Launch System (SLS) rocket to space. During this test, engineers evaluated the engine’s new controller or “brain”, which communicates with the SLS vehicle. Once test data is certified, the engine controller will be removed and installed on one of the four flight engines that will help power the first integrated flight of SLS and the Orion spacecraft.

Interim Cryogenic Propulsion Stage (ICPS) Transport from DOC to

NASA Image and Video Library

2017-07-26

Packed inside its canister, the Interim Cryogenic Propulsion Stage (ICPS) for NASA's Space Launch System (SLS) rocket arrives at the low bay entrance of the Space Station Processing Facility at NASA's Kennedy Space Center in Florida. The ICPS is the first integrated piece of flight hardware to arrive for the SLS. It is the in-space stage that is located toward the top of the rocket, between the Launch Vehicle Stage Adapter and the Orion Spacecraft Adapter. It will provide some of the in-space propulsion during Orion's first flight test atop the SLS on Exploration Mission-1.

Interim Cryogenic Propulsion Stage (ICPS) Transport from DOC to

NASA Image and Video Library

2017-07-26

Packed inside its canister, the Interim Cryogenic Propulsion Stage (ICPS) for NASA's Space Launch System (SLS) rocket is being transported to the Space Station Processing Facility at NASA's Kennedy Space Center in Florida. The ICPS is the first integrated piece of flight hardware to arrive for the SLS. It is the in-space stage that is located toward the top of the rocket, between the Launch Vehicle Stage Adapter and the Orion Spacecraft Adapter. It will provide some of the in-space propulsion during Orion's first flight test atop the SLS on Exploration Mission-1.

Interim Cryogenic Propulsion Stage (ICPS) Transport from DOC to

NASA Image and Video Library

2017-07-26

Packed inside its canister, the Interim Cryogenic Propulsion Stage (ICPS) for NASA's Space Launch System (SLS) rocket is moved into the low bay entrance of the Space Station Processing Facility at NASA's Kennedy Space Center in Florida. The ICPS is the first integrated piece of flight hardware to arrive for the SLS. It is the in-space stage that is located toward the top of the rocket, between the Launch Vehicle Stage Adapter and the Orion Spacecraft Adapter. It will provide some of the in-space propulsion during Orion's first flight test atop the SLS on Exploration Mission-1.

Orion EM-1 Booster Preps - Aft Skirt Preps/Painting

NASA Image and Video Library

2016-10-28

A paint technician with Orbital ATK, prime contractor for the Space Launch System (SLS) Booster, uses an air gun to apply paint to the right hand aft skirt for NASA’s SLS rocket inside a support building at the Hangar AF facility at Cape Canaveral Air Force Station. The space shuttle-era aft skirt, was inspected and resurfaced to prepare it for primer and paint. The aft skirt will be used on the right hand booster of the SLS rocket for Exploration Mission 1 (EM-1). NASA is preparing for EM-1, deep-space missions, and the journey to Mars.

Vehicle Support Posts Installation at Mobile Launcher

NASA Image and Video Library

2017-05-11

Construction workers at the Mobile Launcher at NASA's Kennedy Space Center in Florida, prepare to install vehicle support posts. A total of eight support posts are being installed to support the load of the Space Launch System's (SLS) solid rocket boosters, with four posts for each of the boosters. The support posts are about five feet tall and each weigh about 10,000 pounds. The posts will structurally support the SLS rocket through T-0 and liftoff. The Ground Systems Development and Operations Program is overseeing installation of the support posts to prepare for the launch of the Orion spacecraft atop the SLS rocket.

NASA's Space Launch System: Progress Toward the Proving Ground

NASA Technical Reports Server (NTRS)

Jackman, Angie; Johnson, Les

2017-01-01

With significant and substantial progress being accomplished toward readying the Space Launch System (SLS) rocket for its first test flight, work is already also underway on preparations for the second flight - using an upgraded version of the vehicle - and beyond. SLS is the most powerful human-rated launch vehicle the United States has ever undertaken, and together with the Orion spacecraft will support human exploration missions into the proving ground of cislunar space and ultimately to Mars. This paper will provide a description of the SLS vehicle, and an overview of the vehicle's capabilities and utilization potential.

SLS Overview and Progress

NASA Technical Reports Server (NTRS)

Honeycutt, John

2017-01-01

Space Launch System will be able to offer payload accommodations with five times more volume than any contemporary launch vehicle Payload fairings of up to 10-meter diameter are being studied Space Launch System will offer an initial capability of greater than 70 metric tons to low Earth orbit; current U.S. launch vehicle maximum is 28 t Evolved version of SLS will offer Mars-enabling capability of greater than 130 metric tons to LEO SLS offers reduced transit times to the outer solar system by half or greater Higher characteristic energy (C3) also enables larger payloads to destination

Platform C South Arrival

NASA Image and Video Library

2016-08-05

The second section of the first half of the C-level work platforms, C South, for NASA’s Space Launch System (SLS) rocket was offloaded from a heavy transport truck in a staging area on the west side of the Vehicle Assembly Building (VAB) at the agency’s Kennedy Space Center in Florida. The Ground Systems Development and Operations Program is overseeing upgrades and modifications to VAB High Bay 3 to support processing of the SLS and Orion spacecraft. A total of 10 levels of new platforms, 20 platform halves altogether, will surround the SLS rocket and Orion spacecraft and provide access for testing and processing.

Space Launch System NASA Research Announcement Advanced Booster Engineering Demonstration and/or Risk Reduction

NASA Technical Reports Server (NTRS)

Crumbly, Christopher M.; Craig, Kellie D.

2011-01-01

The intent of the Advanced Booster Engineering Demonstration and/or Risk Reduction (ABEDRR) effort is to: (1) Reduce risks leading to an affordable Advanced Booster that meets the evolved capabilities of SLS (2) Enable competition by mitigating targeted Advanced Booster risks to enhance SLS affordability. Key Concepts (1) Offerors must propose an Advanced Booster concept that meets SLS Program requirements (2) Engineering Demonstration and/or Risk Reduction must relate to the Offeror s Advanced Booster concept (3) NASA Research Announcement (NRA) will not be prescriptive in defining Engineering Demonstration and/or Risk Reduction

Orion Stage Adapter Arrival

NASA Image and Video Library

2018-04-03

NASA's Super Guppy aircraft touches down at the Shuttle Landing Facility at the agency's Kennedy Space Center in Florida. The Super Guppy is carrying the Orion Stage Adapter (OSA), the second flight-hardware section of NASA's Space Launch System (SLS) rocket that has arrived at Kennedy. The OSA will connect the Orion spacecraft to the upper part of the SLS rocket, the interim cryogenic propulsion stage (ICPS). Both the OSA and ICPS are being stored for processing in the center's Space Station Processing Facility in preparation for Exploration Mission-1, the first uncrewed, integrated launch of the SLS rocket and Orion spacecraft.

Orion Stage Adapter Arrival

NASA Image and Video Library

2018-04-03

NASA's Super Guppy aircraft taxies onto the tarmac after touching down at the Shuttle Landing Facility at the agency's Kennedy Space Center in Florida. The Super Guppy is carrying the Orion Stage Adapter (OSA), the second flight-hardware section of NASA's Space Launch System (SLS) rocket that has arrived at Kennedy. The OSA will connect the Orion spacecraft to the upper part of the SLS rocket, the interim cryogenic propulsion stage (ICPS). Both the OSA and ICPS are being stored for processing in the center's Space Station Processing Facility in preparation for Exploration Mission-1, the first uncrewed, integrated launch of the SLS rocket and Orion spacecraft.

Orion Stage Adapter Arrival

NASA Image and Video Library

2018-04-03

NASA's Super Guppy aircraft glides to a stop at the Shuttle Landing Facility at the agency's Kennedy Space Center in Florida. The Super Guppy is carrying the Orion Stage Adapter (OSA), the second flight-hardware section of NASA's Space Launch System (SLS) rocket that has arrived at Kennedy. The OSA will connect the Orion spacecraft to the upper part of the SLS rocket, the interim cryogenic propulsion stage (ICPS). Both the OSA and ICPS are being stored for processing in the center's Space Station Processing Facility in preparation for Exploration Mission-1, the first uncrewed, integrated launch of the SLS rocket and Orion spacecraft.

Orion Stage Adapter Arrival

NASA Image and Video Library

2018-04-03

NASA's Super Guppy aircraft prepares to touch down at the Shuttle Landing Facility at the agency's Kennedy Space Center in Florida. The Super Guppy is carrying the Orion Stage Adapter (OSA), the second flight-hardware section of NASA's Space Launch System (SLS) rocket that has arrived at Kennedy. The OSA will connect the Orion spacecraft to the upper part of the SLS rocket, the interim cryogenic propulsion stage (ICPS). Both the OSA and ICPS are being stored for processing in the center's Space Station Processing Facility in preparation for Exploration Mission-1, the first uncrewed, integrated launch of the SLS rocket and Orion spacecraft.

In vivo assessment of cytological changes by means of reflectance confocal microscopy - demonstration of the effect of topical vitamin E on skin irritation caused by sodium lauryl sulfate.

PubMed

Casari, Alice; Farnetani, Francesca; De Pace, Barbara; Losi, Amanda; Pittet, Jean-Christophe; Pellacani, Giovanni; Longo, Caterina

2017-03-01

Irritant contact dermatitis is caused by skin barrier damage. Vitamin E is an antioxidant that is commonly used in cosmetics to prevent photo-damage. To show the usefulness of reflectance confocal microscopy in the assessment of irritant skin damage caused by sodium lauryl sulfate (SLS) and of the protective action of vitamin E applied prior to skin irritation. Ten healthy volunteers were enrolled. Irritation was induced by the application of a patch test containing SLS 5% aq. for 24 h. Three sites were compared: one site on which a product with vitamin E was applied before SLS treatment, one site on which the same product was applied after SLS treatment, and one control site (SLS only). Each site was evaluated with reflectance confocal microscopy, providing in vivo tissue images at nearly histological resolution. We also performed a computerized analysis of the VivaStack® images. Reflectance confocal microscopy is able to identify signs of skin irritation and the preventive effect of vitamin E application. Reflectance confocal microscopy is useful in the objective assessment of irritative skin damage. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Effectiveness versus efficacy trials in COPD: how study design influences outcomes and applicability.

PubMed

Woodcock, Ashley; Boucot, Isabelle; Leather, David A; Crawford, Jodie; Collier, Susan; Bakerly, Nawar Diar; Hilton, Emma; Vestbo, Jørgen

2018-02-01

Guidelines for chronic obstructive pulmonary disease (COPD) management are based largely on results from double-blind randomised controlled trials (RCTs) of efficacy. These trials have high internal validity and test whether a drug is efficacious, but they are conducted in highly selected populations that may differ significantly from patients with COPD seen in routine practice.We compared the baseline characteristics, healthcare use and outcomes between the Salford Lung Study (SLS), an open-label effectiveness RCT, with six recent large-scale efficacy RCTs. We also calculated the proportion of SLS patients who would have been eligible for inclusion in an efficacy RCT by applying the inclusion criteria used in efficacy trials of combination treatments.SLS patients were older, included more females and more current smokers, had more comorbidities (including asthma), and had more often experienced exacerbations prior to inclusion. In the SLS, rates of moderate or severe exacerbations, incidence of overall serious adverse events (SAEs), and SAEs of pneumonia were more frequent. A maximum of 30% of patients enrolled in the SLS would have been eligible for a phase IIIa regulatory exacerbation study.Patients in large COPD efficacy RCTs have limited representativeness compared with an effectiveness trial. This should be considered when interpreting efficacy RCT outcomes and their inclusion into guidelines. Copyright ©ERS 2018.

InGaAs/InAsSb strained layer superlattices for mid-wave infrared detectors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ariyawansa, Gamini, E-mail: gamini.ariyawansa.2@us.af.mil; Reyner, Charles J.; Steenbergen, Elizabeth H.

2016-01-11

Investigation of growth and properties of InGaAs/InAsSb strained layer superlattices, identified as ternary strained layer superlattices (ternary SLSs), is reported. The material space for the antimony-based SLS detector development is expanded beyond InAs/InAsSb and InAs/(In)GaSb by incorporating Ga into InAs. It was found that this not only provides support for strain compensation but also enhances the infrared (IR) absorption properties. A unique InGaAs/InAsSb SLS exists when the conduction band of InGaAs aligns with that of InAsSb. The bandgap of this specific InGaAs/InAsSb SLS can then be tuned by adjusting the thickness of both constituents. Due to the enhanced electron-hole wavefunctionmore » overlap, a significant increase in the absorption coefficient was theoretically predicted for ternary SLS as compared to current state-of-the-art InAs/InAsSb SLS structures, and an approximately 30%–35% increase in the absorption coefficient was experimentally observed. All the samples examined in this work were designed to have the same bandgap of approximately 0.240 eV (5.6 μm) at 150 K.« less

Aluminum 2195 T8 Gore Development for Space Launch System Core and Upper Stage

NASA Technical Reports Server (NTRS)

Volz, Martin

2015-01-01

Gores are pie-shaped panels that are welded together to form the dome ends of rocket fuel tanks as shown in figure 1. Replacing aluminum alloy 2219 with aluminum (Al)-lithium (Li) alloy 2195 as the Space Launch System (SLS) cryogenic tank material would save enormous amounts of weight. In fact, it has been calculated that simply replacing Al 2219 gores with Al 2195 gores on the SLS core stage domes could save approximately 3,800 pound-mass. This is because the Al-Li 2195 alloy exhibits both higher mechanical properties and lower density than the SLS baseline Al 2219 alloy. Indeed, the known advantages of Al 2195 led to its use as a replacement for Al 2219 in the shuttle external tank program. The required thicknesses of Al 2195 gores for either SLS core stage tanks or upper stage tanks will depend on the specific design configurations. The required thicknesses or widths may exceed the current experience base in the manufacture of such gores by the stretch-forming process. Accordingly, the primary objective of this project was to enhance the formability of Al 2195 by optimizing the heat treatment and stretch-forming process for gore thicknesses up to 0.75 inches, which envelop the maximum expected gore thicknesses for SLS tank configurations.

Localization of 1-deoxysphingolipids to mitochondria induces mitochondrial dysfunction[S

PubMed Central

Alecu, Irina; Tedeschi, Andrea; Behler, Natascha; Wunderling, Klaus; Lamberz, Christian; Lauterbach, Mario A. R.; Gaebler, Anne; Ernst, Daniela; Van Veldhoven, Paul P.; Al-Amoudi, Ashraf; Latz, Eicke; Othman, Alaa; Kuerschner, Lars; Hornemann, Thorsten; Bradke, Frank; Thiele, Christoph; Penno, Anke

2017-01-01

1-Deoxysphingolipids (deoxySLs) are atypical sphingolipids that are elevated in the plasma of patients with type 2 diabetes and hereditary sensory and autonomic neuropathy type 1 (HSAN1). Clinically, diabetic neuropathy and HSAN1 are very similar, suggesting the involvement of deoxySLs in the pathology of both diseases. However, very little is known about the biology of these lipids and the underlying pathomechanism. We synthesized an alkyne analog of 1-deoxysphinganine (doxSA), the metabolic precursor of all deoxySLs, to trace the metabolism and localization of deoxySLs. Our results indicate that the metabolism of these lipids is restricted to only some lipid species and that they are not converted to canonical sphingolipids or fatty acids. Furthermore, exogenously added alkyne-doxSA [(2S,3R)-2-aminooctadec-17-yn-3-ol] localized to mitochondria, causing mitochondrial fragmentation and dysfunction. The induced mitochondrial toxicity was also shown for natural doxSA, but not for sphinganine, and was rescued by inhibition of ceramide synthase activity. Our findings therefore indicate that mitochondrial enrichment of an N-acylated doxSA metabolite may contribute to the neurotoxicity seen in diabetic neuropathy and HSAN1. Hence, we provide a potential explanation for the characteristic vulnerability of peripheral nerves to elevated levels of deoxySLs. PMID:27881717

Synthesis of 1,3-dioleoyl-2-arachidonoylglycerol-rich structured lipids by lipase-catalyzed acidolysis of microbial oil from Mortierella alpina.

PubMed

Abed, Sherif M; Zou, Xiaoqiang; Ali, Abdelmoneim H; Jin, Qingzhe; Wang, Xingguo

2017-11-01

Microbial oils (MOs) have gained widespread attention due to their functional lipids and health promoting properties. In this study, 1,3-dioleoyl-2-arachidonoylglycerol-rich structured lipids (SLs) were produced from MO and oleic acid (OA) via solvent-free acidolysis catalyzed by Lipozyme RM IM. Under the optimal conditions, the content of unsaturated fatty acids (UFAs) increased from 60.63 to 84.00%, while the saturated fatty acids (SFAs) content decreased from 39.37 to 16.00% at sn-1,3 positions in SLs. Compared with MO, arachidonic acid (ARA) content at the sn-2 position of SLs accounted for 49.71%, whereas OA was predominantly located at sn-1,3 positions (47.05%). Meanwhile, the most abundant triacylglycerol (TAG) species in SLs were (18:1-20:4-18:1), (20:4-20:4-18:1), (18:1-18:2-18:1), (18:1-18:2-18:0) and (24:0-20:4-18:1) with a relative content of 18.79%, 11.94%, 6.07%, 5.75% and 4.84%, respectively. Such novel SLs with improved functional properties enriched with UFAs are highly desirable and have the potential to be used in infant formula. Copyright © 2017 Elsevier Ltd. All rights reserved.

Spray-dried structured lipid containing long-chain polyunsaturated fatty acids for use in infant formulas.

PubMed

Nagachinta, Supakana; Akoh, Casimir C

2013-10-01

Human milk fat (HMF) analogs are structured lipids (SLs) modified to have palmitic acid content at the sn-2 position of the triacylglycerol (TAG) and fatty acid composition comparable to HMF. Some of these SLs are also designed to incorporate long-chain polyunsaturated fatty acids (LCPUFAs) because of their important role in infant development. In this study, Maillard reaction products (MRPs), obtained from heated whey protein isolates and corn syrup solids (CSS) solution, were used as encapsulants for microencapsulation of 2 enzymatically synthesized SLs for infant formula applications. The encapsulated SL powders were obtained through spray-drying and evaluated in terms of their microencapsulation efficiency, chemical and physical properties, oxidative stability, and dispersibility. The microencapsulation efficiency of the SLs was 90%. Dispersibility test using particle size measurement demonstrated that these powders dispersed quickly into a homogeneous suspension. The encapsulated SL powders had low peroxide and thiobarbituric acid-reactive substances values. Lower oxidative stability was obtained in the powder containing SL with a higher degree of unsaturation and a lower concentration of tocopherols. The results demonstrated that the degree of fatty acid unsaturation and concentration of endogenous antioxidant in starting oils influenced the oxidative stability of the encapsulated SLs. © 2013 Institute of Food Technologists®

NASA's Space Launch System Progress Report

NASA Technical Reports Server (NTRS)

Singer, Joan A.; Cook, Jerry R.; Lyles, Garry M.; Beaman, David E.

2011-01-01

Exploration beyond Earth will be an enduring legacy for future generations, confirming America's commitment to explore, learn, and progress. NASA's Space Launch System (SLS) Program, managed at the Marshall Space Flight Center, is responsible for designing and developing the first exploration-class rocket since the Apollo Program's Saturn V that sent Americans to the Moon. The SLS offers a flexible design that may be configured for the MultiPurpose Crew Vehicle and associated equipment, or may be outfitted with a payload fairing that will accommodate flagship science instruments and a variety of high-priority experiments. Both options support a national capability that will pay dividends for future generations. Building on legacy systems, facilities, and expertise, the SLS will have an initial lift capability of 70 metric tons (mT) and will be evolvable to 130 mT. While commercial launch vehicle providers service the International Space Station market, this capability will surpass all vehicles, past and present, providing the means to do entirely new missions, such as human exploration of asteroids and Mars. With its superior lift capability, the SLS can expand the interplanetary highway to many possible destinations, conducting revolutionary missions that will change the way we view ourselves, our planet and its place in the cosmos. To perform missions such as these, the SLS will be the largest launch vehicle ever built. It is being designed for safety and affordability - to sustain our journey into the space age. Current plans include launching the first flight, without crew, later this decade, with crewed flights beginning early next decade. Development work now in progress is based on heritage space systems and working knowledge, allowing for a relatively quick start and for maturing the SLS rocket as future technologies become available. Together, NASA and the U.S. aerospace industry are partnering to develop this one-of-a-kind asset. Many of NASA's space centers across the country will provide their unique expertise to the Space Launch System endeavor. Unique infrastructure to be used includes the Michoud Assembly Facility for tank manufacturing, Stennis Space Center for engine testing, and Kennedy Space Center for processing and launch. As this panel will discuss, the SLS team is dedicated to doing things differently-from applying lean oversight/insight models to smartly using legacy hardware and existing facilities. Building on the foundation laid by over 50 years of human and scientific space flight--and on the lessons learned from the Apollo, Space Shuttle, and Constellation Programs-the SLS team has delivered both technical trade studies and business case analyses to ensure that the SLS architecture will be safe, affordable, reliable, and sustainable.

Bottom-water oxygenation and environmental change in Santa Monica Basin, southern California during the last 22 kyr

DOE Office of Scientific and Technical Information (OSTI.GOV)

Balestra, Barbara; Krupinksi, Nadine Quintana; Erhoina, Tzvetina

The Southern California Borderland (SCB) is a region that experiences strong natural variations in bottom water oxygen and pH. Here, we use marine sediments from the Santa Monica Basin (SMB) to reconstruct environmental conditions and changes in the basin's bottom water oxygenation from the Last Glacial Maximum (LGM) to present, and compare the records to the adjacent Santa Barbara Basin (SBB) and Santa Lucia Slope (SLS). High-resolution records of benthic foraminiferal oxygen and carbon isotopes (δ 18O and δ 13C), benthic foraminiferal assemblages, and bulk sedimentary organic matter geochemistry records exhibit major changes associated with late Quaternary millennial-scale global climatemore » oscillations. Our data show the dominance of low-oxygen benthic foraminifera assemblages during warm intervals, and assemblages representing higher dissolved oxygen during cooler intervals, as also seen in SBB and SLS. But, our record shows a stronger and longer-lasting oxygen minimum zone (OMZ) between the end of the Bølling-Allerød (B-A) and the Early Holocene (including the Younger Dryas) than at neighboring sites, indicated by dominance of Bolivina tumida (characteristic of major hypoxia) in the assemblage. The middle to late Holocene (from ~ 8.8 to 0 ka) had weaker hypoxia than the early Holocene, with assemblages mainly composed of Bolivina argentea and Uvigerina peregrina. The SMB remains mostly slightly low in oxygen throughout the studied interval, with differences in the degree of hypoxia relative to SBB and SLS (especially from the B-A to the Early Holocene) likely due to its greater depth and its more southern geographic position and therefore decreased exposure to North Pacific Intermediate Water current. Regional effects, such as changing intermediate water source and/or changing ventilation (oxygenation) of the intermediate water source, also affect SMB deep water. Our analysis utilizing parallel geochemical and micropaleontological records brings new insights into bottom water and climate conditions in SMB, indicating regional similarities and differences with adjacent basins, and provides insight into the causes for changes in bottom water oxygenation.« less

Bottom-water oxygenation and environmental change in Santa Monica Basin, southern California during the last 22 kyr

DOE PAGES

Balestra, Barbara; Krupinksi, Nadine Quintana; Erhoina, Tzvetina; ...

2017-09-29

The Southern California Borderland (SCB) is a region that experiences strong natural variations in bottom water oxygen and pH. Here, we use marine sediments from the Santa Monica Basin (SMB) to reconstruct environmental conditions and changes in the basin's bottom water oxygenation from the Last Glacial Maximum (LGM) to present, and compare the records to the adjacent Santa Barbara Basin (SBB) and Santa Lucia Slope (SLS). High-resolution records of benthic foraminiferal oxygen and carbon isotopes (δ 18O and δ 13C), benthic foraminiferal assemblages, and bulk sedimentary organic matter geochemistry records exhibit major changes associated with late Quaternary millennial-scale global climatemore » oscillations. Our data show the dominance of low-oxygen benthic foraminifera assemblages during warm intervals, and assemblages representing higher dissolved oxygen during cooler intervals, as also seen in SBB and SLS. But, our record shows a stronger and longer-lasting oxygen minimum zone (OMZ) between the end of the Bølling-Allerød (B-A) and the Early Holocene (including the Younger Dryas) than at neighboring sites, indicated by dominance of Bolivina tumida (characteristic of major hypoxia) in the assemblage. The middle to late Holocene (from ~ 8.8 to 0 ka) had weaker hypoxia than the early Holocene, with assemblages mainly composed of Bolivina argentea and Uvigerina peregrina. The SMB remains mostly slightly low in oxygen throughout the studied interval, with differences in the degree of hypoxia relative to SBB and SLS (especially from the B-A to the Early Holocene) likely due to its greater depth and its more southern geographic position and therefore decreased exposure to North Pacific Intermediate Water current. Regional effects, such as changing intermediate water source and/or changing ventilation (oxygenation) of the intermediate water source, also affect SMB deep water. Our analysis utilizing parallel geochemical and micropaleontological records brings new insights into bottom water and climate conditions in SMB, indicating regional similarities and differences with adjacent basins, and provides insight into the causes for changes in bottom water oxygenation.« less

Estimating Noise Levels In An Enclosed Space

NASA Technical Reports Server (NTRS)

Azzi, Elias

1995-01-01

GEGS Acoustic Analysis Program (GAAP) developed to compute composite profile of noise in Spacelab module on basis of data on noise produced by equipment, data on locations of equipment, and equipment-operating schedules. Impetus for development of GAAP provided by noise that generated in Spacelab Module during SLS-1 mission because of concurrent operation of many pieces of experimental and subsystem equipment. Although originally intended specifically to help compute noise in Spacelab, also applicable to any region with multiple sources of noise. Written in FORTRAN 77.

Astronaut David Wolf draws blood from Martin Fettman for SLS-2 investigations

NASA Technical Reports Server (NTRS)

1993-01-01

Inside the science module aboard the Earth-orbiting Space Shuttle Columbia, Astronaut David A. Wolf draws blood from payload specialists Martin J. Fettman, DVM. Blood samples from crew members are critical to several Spacelab Life Sciences (SLS-2) investigations.

BIOMEDICAL - MEDICAL (ECHOCARDIOGRAPH) - JSC

NASA Image and Video Library

1987-03-12

S87-28936 (March 1987) --- The Spacelab Life Sciences-1 (SLS-1) echocardiograph, installed in a science module rack, displays the image of a human heart. One of the objectives on SLS-1 is the investigation of the effects of microgravity on heart size and function.

Synthesis and evaluation of the service limit state of engineered fills for bridge support.

DOT National Transportation Integrated Search

2016-02-02

This report synthesizes the current service limit state (SLS) design and analyses of engineered fills for bridge support used as shallow foundations. The SLS for settlement and deformations of bridge supports are summarized. Extensive literature revi...

Self-assembly of block copolymer micelles: synthesis via reversible addition-fragmentation chain transfer polymerization and aqueous solution properties.

PubMed

Mya, Khine Y; Lin, Esther M J; Gudipati, Chakravarthy S; Gose, Halima B A S; He, Chaobin

2010-07-22

Poly(hexafluorobutyl methacrylate) (PHFBMA) homopolymer was synthesized by reversible addition-fragmentation chain transfer (RAFT)-mediated living radical polymerization in the presence of cyano-2-propyl dithiobenzoate (CPDB) RAFT agent. A block copolymer of PHFBMA-poly(propylene glycol acrylate) (PHFBMA-b-PPGA) with dangling poly(propylene glycol) (PPG) side chains was then synthesized by using CPDB-terminated PHFBMA as a macro-RAFT agent. The amphiphilic properties and self-assembly of PHFBMA-b-PPGA block copolymer in aqueous solution were investigated by dynamic and static light scattering (DLS and SLS) studies, in combination with fluorescence spectroscopy and transmission electron microscopy (TEM). Although PPG shows moderately hydrophilic character, the formation of nanosize polymeric micelles was confirmed by fluorescence and TEM studies. The low value of the critical aggregation concentration exhibited that the tendency for the formation of copolymer aggregates in aqueous solution was very high due to the strong hydrophobicity of the PHFBMA(145)-b-PPGA(33) block copolymer. The combination of DLS and SLS measurements revealed the existence of micellar aggregates in aqueous solution with an association number of approximately 40 +/- 7 for block copolymer micelles. It was also found in TEM observation that there are 40-50 micelles accumulated into one aggregate and these micelles are loosely packed inside the aggregate.

Solution-mediated phase transformation of haloperidol mesylate in the presence of sodium lauryl sulfate.

PubMed

Greco, Kristyn; Bogner, Robin

2011-09-01

Forming a salt is a common way to increase the solubility of a poorly soluble compound. However, the solubility enhancement gained by salt formation may be lost due to solution-mediated phase transformation (SMPT) during dissolution. The SMPT of a salt can occur due to a supersaturated solution near the dissolving surface caused by pH or other solution conditions. In addition to changes in pH, surfactants are also known to affect SMPT. In this study, SMPT of a highly soluble salt, haloperidol mesylate, at pH 7 in the presence of a commonly used surfactant, sodium lauryl sulfate (SLS), was investigated. Dissolution experiments were performed using a flow-through dissolution apparatus with solutions containing various concentrations of SLS. Compacts of haloperidol mesylate were observed during dissolution in the flow-through apparatus using a stereomicroscope. Raman microscopy was used to characterize solids. The dissolution of haloperidol mesylate was significantly influenced by the addition of sodium lauryl sulfate. In conditions where SMPT was expected, the addition of SLS at low concentrations (0.1-0.2 mM) reduced the dissolution of haloperidol mesylate. In solutions containing concentrations of SLS above the critical micelle concentration (CMC) (10-15 mM), the dissolution of haloperidol mesylate increased compared to below the CMC. The solids recovered from solubility experiments of haloperidol mesylate indicated that haloperidol free base precipitated at all concentrations of SLS. Above 5 mM of SLS, Raman microscopy suggested a new form, perhaps the estolate salt. The addition of surfactant in solids that undergo solution-mediated phase transformation can add complexity to the dissolution profiles and conversion.

Evaluation of Sensible Heat Flux and Evapotranspiration Estimates Using a Surface Layer Scintillometer and a Large Weighing Lysimeter

PubMed Central

Moorhead, Jerry E.; Marek, Gary W.; Colaizzi, Paul D.; Gowda, Prasanna H.; Evett, Steven R.; Brauer, David K.; Marek, Thomas H.; Porter, Dana O.

2017-01-01

Accurate estimates of actual crop evapotranspiration (ET) are important for optimal irrigation water management, especially in arid and semi-arid regions. Common ET sensing methods include Bowen Ratio, Eddy Covariance (EC), and scintillometers. Large weighing lysimeters are considered the ultimate standard for measurement of ET, however, they are expensive to install and maintain. Although EC and scintillometers are less costly and relatively portable, EC has known energy balance closure discrepancies. Previous scintillometer studies used EC for ground-truthing, but no studies considered weighing lysimeters. In this study, a Surface Layer Scintillometer (SLS) was evaluated for accuracy in determining ET as well as sensible and latent heat fluxes, as compared to a large weighing lysimeter in Bushland, TX. The SLS was installed over irrigated grain sorghum (Sorghum bicolor (L.) Moench) for the period 29 July–17 August 2015 and over grain corn (Zea mays L.) for the period 23 June–2 October 2016. Results showed poor correlation for sensible heat flux, but much better correlation with ET, with r2 values of 0.83 and 0.87 for hourly and daily ET, respectively. The accuracy of the SLS was comparable to other ET sensing instruments with an RMSE of 0.13 mm·h−1 (31%) for hourly ET; however, summing hourly values to a daily time step reduced the ET error to 14% (0.75 mm·d−1). This level of accuracy indicates that potential exists for the SLS to be used in some water management applications. As few studies have been conducted to evaluate the SLS for ET estimation, or in combination with lysimetric data, further evaluations would be beneficial to investigate the applicability of the SLS in water resources management. PMID:29036926

NASA's Space Launch System: Building a New Capability for Discovery

NASA Technical Reports Server (NTRS)

Creech, Stephen D.; Robinson, Kimberly F.

2015-01-01

Designed to enable human space exploration missions, including eventually landings on Mars, NASA's Space Launch System (SLS) represents a unique launch capability with a wide range of utilization opportunities, from delivering habitation systems into the lunar vicinity to high-energy transits through the outer solar system. Substantial progress has been made toward the first launch of the initial configuration of SLS, which will be able to deliver more than 70 metric tons of payload into low Earth orbit (LEO). The vehicle will then be evolved into more powerful configurations, culminating with the capability to deliver more than 130 metric tons to LEO. The initial configuration will be able to deliver greater mass to orbit than any contemporary launch vehicle, and the evolved configuration will have greater performance than the Saturn V rocket that enabled human landings on the moon. SLS will also be able to carry larger payload fairings than any contemporary launch vehicle, and will offer opportunities for co-manifested and secondary payloads. Because of its substantial mass-lift capability, SLS will also offer unrivaled departure energy, enabling mission profiles currently not possible. The basic capabilities of SLS have been driven by studies on the requirements of human deep-space exploration missions, and continue to be validated by maturing analysis of Mars mission options. Early collaboration with science teams planning future decadal-class missions have contributed to a greater understanding of the vehicle's potential range of utilization. As this paper will explain, SLS is making measurable progress toward becoming a global infrastructure asset for robotic and human scouts of all nations by providing the robust space launch capability to deliver sustainable solutions for exploration.

Our Human Journey to Mars - The Next Steps

NASA Technical Reports Server (NTRS)

Singer, Jody

2016-01-01

The United States National Aeronautics and Space Administration (NASA) will be launching the super-heavy-lift Space Launch System (SLS) by the end of the decade. This launch marks the next steps of human exploration of Mars and continues the journey that began over 50 years ago with Mariner and most recently ExoMars. SLS is the only rocket with the power capable of sending humans to deep space and the large systems necessary for human exploration all the way to Mars. Exploration Mission (EM)-1 will be the first integrated flight of the SLS rocket and Orion spacecraft - journeying farther into space than Apollo. NASA will also expand the science and exploration capability of SLS by deploying thirteen small satellites into deep space for the first time. These small satellites, created through partnerships with small businesses, Universities and international partners, will carry out various scientific missions to better understand our universe and the challenges of living and working in deep space. SLS EM-1 will provide the framework and serve as a test flight, not only for vehicle systems, but also for payload accommodations, ground processing and on-orbit operations. The results of this mission will validate capabilities for sending explorers to Mars and create the opportunity to pioneer solutions to challenges to deep space exploration. SLS's versatile design will evolve for future exploration needs and accommodate bigger payloads, such as large aperture telescopes for scientific research or manned human deep space exploration missions to Mars. The achievement of EM-1 will demonstrate NASA's commitment and capability to extend human existence to deep space and inspire the world to pursue greatness in the exploration of our universe.

Space Launch System Implementation of Adaptive Augmenting Control

NASA Technical Reports Server (NTRS)

VanZwieten, Tannen S.; Wall, John H.; Orr, Jeb S.

2014-01-01

Given the complex structural dynamics, challenging ascent performance requirements, and rigorous flight certification constraints owing to its manned capability, the NASA Space Launch System (SLS) launch vehicle requires a proven thrust vector control algorithm design with highly optimized parameters to robustly demonstrate stable and high performance flight. On its development path to preliminary design review (PDR), the stability of the SLS flight control system has been challenged by significant vehicle flexibility, aerodynamics, and sloshing propellant dynamics. While the design has been able to meet all robust stability criteria, it has done so with little excess margin. Through significant development work, an adaptive augmenting control (AAC) algorithm previously presented by Orr and VanZwieten, has been shown to extend the envelope of failures and flight anomalies for which the SLS control system can accommodate while maintaining a direct link to flight control stability criteria (e.g. gain & phase margin). In this paper, the work performed to mature the AAC algorithm as a baseline component of the SLS flight control system is presented. The progress to date has brought the algorithm design to the PDR level of maturity. The algorithm has been extended to augment the SLS digital 3-axis autopilot, including existing load-relief elements, and necessary steps for integration with the production flight software prototype have been implemented. Several updates to the adaptive algorithm to increase its performance, decrease its sensitivity to expected external commands, and safeguard against limitations in the digital implementation are discussed with illustrating results. Monte Carlo simulations and selected stressing case results are shown to demonstrate the algorithm's ability to increase the robustness of the integrated SLS flight control system.

NASA'S Space Launch System Mission Capabilities for Exploration

NASA Technical Reports Server (NTRS)

Creech, Stephen D.; Crumbly, Christopher M.; Robinson, Kimberly F.

2015-01-01

Designed to enable human space exploration missions, including eventual landings on Mars, NASA’s Space Launch System (SLS) represents a unique launch capability with a wide range of utilization opportunities, from delivering habitation systems into the lunar vicinity to high-energy transits through the outer solar system. Developed with the goals of safety, affordability and sustainability in mind, SLS is a foundational capability for NASA’s future plans for exploration, along with the Orion crew vehicle and upgraded ground systems at the agency’s Kennedy Space Center. Substantial progress has been made toward the first launch of the initial configuration of SLS, which will be able to deliver more than 70 metric tons of payload into low Earth orbit (LEO), greater mass-to-orbit capability than any contemporary launch vehicle. The vehicle will then be evolved into more powerful configurations, culminating with the capability to deliver more than 130 metric tons to LEO, greater even than the Saturn V rocket that enabled human landings on the moon. SLS will also be able to carry larger payload fairings than any contemporary launch vehicle, and will offer opportunities for co-manifested and secondary payloads. Because of its substantial mass-lift capability, SLS will also offer unrivaled departure energy, enabling mission profiles currently not possible. Early collaboration with science teams planning future decadal-class missions have contributed to a greater understanding of the vehicle’s potential range of utilization. This presentation will discuss the potential opportunities this vehicle poses for the planetary sciences community, relating the vehicle’s evolution to practical implications for mission capture. As this paper will explain, SLS will be a global launch infrastructure asset, employing sustainable solutions and technological innovations to deliver capabilities for space exploration to power human and robotic systems beyond our Moon and in to deep space.

NASA's Space Launch System Mission Capabilities for Exploration

NASA Technical Reports Server (NTRS)

Creech, Stephen D.; Crumbly, Christopher M.; Robinson, Kimberly F.

2015-01-01

Designed to enable human space exploration missions, including eventual landings on Mars, NASA's Space Launch System (SLS) represents a unique launch capability with a wide range of utilization opportunities, from delivering habitation systems into the lunar vicinity to high-energy transits through the outer solar system. Developed with the goals of safety, affordability and sustainability in mind, SLS is a foundational capability for NASA's future plans for exploration, along with the Orion crew vehicle and upgraded ground systems at the agency's Kennedy Space Center. Substantial progress has been made toward the first launch of the initial configuration of SLS, which will be able to deliver more than 70 metric tons of payload into low Earth orbit (LEO), greater mass-to-orbit capability than any contemporary launch vehicle. The vehicle will then be evolved into more powerful configurations, culminating with the capability to deliver more than 130 metric tons to LEO, greater even than the Saturn V rocket that enabled human landings on the moon. SLS will also be able to carry larger payload fairings than any contemporary launch vehicle, and will offer opportunities for co-manifested and secondary payloads. Because of its substantial mass-lift capability, SLS will also offer unrivaled departure energy, enabling mission profiles currently not possible. Early collaboration with science teams planning future decadal-class missions have contributed to a greater understanding of the vehicle's potential range of utilization. This presentation will discuss the potential opportunities this vehicle poses for the planetary sciences community, relating the vehicle's evolution to practical implications for mission capture. As this paper will explain, SLS will be a global launch infrastructure asset, employing sustainable solutions and technological innovations to deliver capabilities for space exploration to power human and robotic systems beyond our Moon and in to deep space.

Evaluation of Sensible Heat Flux and Evapotranspiration Estimates Using a Surface Layer Scintillometer and a Large Weighing Lysimeter.

PubMed

Moorhead, Jerry E; Marek, Gary W; Colaizzi, Paul D; Gowda, Prasanna H; Evett, Steven R; Brauer, David K; Marek, Thomas H; Porter, Dana O

2017-10-14

Accurate estimates of actual crop evapotranspiration (ET) are important for optimal irrigation water management, especially in arid and semi-arid regions. Common ET sensing methods include Bowen Ratio, Eddy Covariance (EC), and scintillometers. Large weighing lysimeters are considered the ultimate standard for measurement of ET, however, they are expensive to install and maintain. Although EC and scintillometers are less costly and relatively portable, EC has known energy balance closure discrepancies. Previous scintillometer studies used EC for ground-truthing, but no studies considered weighing lysimeters. In this study, a Surface Layer Scintillometer (SLS) was evaluated for accuracy in determining ET as well as sensible and latent heat fluxes, as compared to a large weighing lysimeter in Bushland, TX. The SLS was installed over irrigated grain sorghum ( Sorghum bicolor (L.) Moench) for the period 29 July-17 August 2015 and over grain corn ( Zea mays L.) for the period 23 June-2 October 2016. Results showed poor correlation for sensible heat flux, but much better correlation with ET, with r² values of 0.83 and 0.87 for hourly and daily ET, respectively. The accuracy of the SLS was comparable to other ET sensing instruments with an RMSE of 0.13 mm·h -1 (31%) for hourly ET; however, summing hourly values to a daily time step reduced the ET error to 14% (0.75 mm·d -1 ). This level of accuracy indicates that potential exists for the SLS to be used in some water management applications. As few studies have been conducted to evaluate the SLS for ET estimation, or in combination with lysimetric data, further evaluations would be beneficial to investigate the applicability of the SLS in water resources management.

NASA's Space Launch System Takes Shape: Progress Toward Safe, Affordable, Exploration

NASA Technical Reports Server (NTRS)

Askins, Bruce R.; Robinson, Kimberly F.

2014-01-01

Development of NASA's Space Launch System (SLS) exploration-class heavy lift rocket has moved from the formulation phase to implementation in 3 years and will make significant progress this year toward its first launch, slated December 2017. SLS represents a safe, affordable, and evolutionary path to development of an unprecedented capability for future human and robotic exploration and use of space. For the United States current development is focused on a configuration with a 70 metric ton (t) payload to low Earth orbit (LEO), more than double any operational vehicle. This version will launch NASA's Orion Multi-Purpose Crew Vehicle (MPCV) on its first autonomous flight beyond the Moon and back, as well as the first crewed Orion flight. SLS is designed to evolve to a 130 t lift capability that can reduce mission costs, simplify payload design, reduce trip times, and lower overall risk. Each vehicle element completed its respective Preliminary Design Reviews, followed by the SLS Program. The Program also completed the Key Decision Point-C milestone to move from formulation to implementation in 2014. NASA hasthorized the program to proceed to Critical Design Review, scheduled for 2015. Accomplihments to date include: manufacture of core stage test hardware, as well as preparations for testing the world's most powerful solid rocket boosters and main engines that flew 135 successful Space Shuttle missions. The Program's success to date is due to prudent use of existing technology, infrastructure, and workforce; streamlined management approach; and judicious use of new technologies. This paper will discuss SLS Program successes over the past year and examine milestones and challenges ahead. The SLS Program and its elements are managed at NASA's Marshall Space Flight Center (MSFC).

NASA's Space Launch System: An Evolving Capability for Exploration

NASA Technical Reports Server (NTRS)

Creech, Stephen D.; Robinson, Kimberly F.

2016-01-01

A foundational capability for international human deep-space exploration, NASA's Space Launch System (SLS) vehicle represents a new spaceflight infrastructure asset, creating opportunities for mission profiles and space systems that cannot currently be executed. While the primary purpose of SLS, which is making rapid progress towards initial launch readiness in two years, will be to support NASA's Journey to Mars, discussions are already well underway regarding other potential utilization of the vehicle's unique capabilities. In its initial Block 1 configuration, capable of launching 70 metric tons (t) to low Earth orbit (LEO), SLS will propel the Orion crew vehicle to cislunar space, while also delivering small CubeSat-class spacecraft to deep-space destinations. With the addition of a more powerful upper stage, the Block 1B configuration of SLS will be able to deliver 105 t to LEO and enable more ambitious human missions into the proving ground of space. This configuration offers opportunities for launching co-manifested payloads with the Orion crew vehicle, and a class of secondary payloads, larger than today's CubeSats. Further upgrades to the vehicle, including advanced boosters, will evolve its performance to 130 t in its Block 2 configuration. Both Block 1B and Block 2 also offer the capability to carry 8.4- or 10-m payload fairings, larger than any contemporary launch vehicle. With unmatched mass-lift capability, payload volume, and C3, SLS not only enables spacecraft or mission designs currently impossible with contemporary EELVs, it also offers enhancing benefits, such as reduced risk, operational costs and/or complexity, shorter transit time to destination or launching large systems either monolithically or in fewer components. This paper will discuss both the performance and capabilities of Space Launch System as it evolves, and the current state of SLS utilization planning.

Comparative Study of Mechanisms of Herpes Simplex Virus Inactivation by Sodium Lauryl Sulfate and n-Lauroylsarcosine

PubMed Central

Piret, Jocelyne; Roy, Sylvie; Gagnon, Mylène; Landry, Sébastien; Désormeaux, André; Omar, Rabeea F.; Bergeron, Michel G.

2002-01-01

The mechanisms of herpes simplex virus (HSV) inactivation by sodium lauryl sulfate (SLS) and n-lauroylsarcosine (LS), two anionic surfactants with protein denaturant potency, have been evaluated in cultured cells. Results showed that pretreatment of HSV type 1 (HSV-1) strain F and HSV-2 strain 333 with either surfactant inhibited, in a concentration- and time-dependent manner, their infectivities on Vero cells. SLS was a more potent inhibitor of HSV-2 strain 333 infectivity than LS with respect to the concentration (4.8-fold lower) and time (2.4-fold shorter) required to completely inactivate the virus. No inhibition of both herpesvirus strains infectivities was observed when Vero cells were pretreated with either surfactant. LS prevented the binding of HSV-2 strain 333 to cells without affecting the stable attachment and the rate of penetration into cells, whereas SLS exerted the opposite effect. Both SLS and LS inhibited, in a concentration-dependent manner, the HSV-2 strain 333-induced cytopathic effect, probably by affecting newly synthesized virions that come into contact with surfactant molecules present in culture medium. The pretreatment of HSV-2 strain 333 with specific combinations of SLS and LS concentrations inhibited the viral infectivity in a synergistic manner and resulted in only a small increase in their toxicities for exponentially growing Vero cells compared with that caused by each compound alone. Taken together, these results suggest that SLS and LS, alone or combined, could represent potent candidates as microbicides in topical vaginal formulations to prevent the transmission of herpes and possibly other pathogens that cause sexually transmitted diseases, including human immunodeficiency virus type 1. PMID:12183250

Leading for the long haul: a mixed-method evaluation of the Sustainment Leadership Scale (SLS).

PubMed

Ehrhart, Mark G; Torres, Elisa M; Green, Amy E; Trott, Elise M; Willging, Cathleen E; Moullin, Joanna C; Aarons, Gregory A

2018-01-19

Despite our progress in understanding the organizational context for implementation and specifically the role of leadership in implementation, its role in sustainment has received little attention. This paper took a mixed-method approach to examine leadership during the sustainment phase of the Exploration, Preparation, Implementation, Sustainment (EPIS) framework. Utilizing the Implementation Leadership Scale as a foundation, we sought to develop a short, practical measure of sustainment leadership that can be used for both applied and research purposes. Data for this study were collected as a part of a larger mixed-method study of evidence-based intervention, SafeCare®, sustainment. Quantitative data were collected from 157 providers using web-based surveys. Confirmatory factor analysis was used to examine the factor structure of the Sustainment Leadership Scale (SLS). Qualitative data were collected from 95 providers who participated in one of 15 focus groups. A framework approach guided qualitative data analysis. Mixed-method integration was also utilized to examine convergence of quantitative and qualitative findings. Confirmatory factor analysis supported the a priori higher order factor structure of the SLS with subscales indicating a single higher order sustainment leadership factor. The SLS demonstrated excellent internal consistency reliability. Qualitative analyses offered support for the dimensions of sustainment leadership captured by the quantitative measure, in addition to uncovering a fifth possible factor, available leadership. This study found qualitative and quantitative support for the pragmatic SLS measure. The SLS can be used for assessing leadership of first-level leaders to understand how staff perceive leadership during sustainment and to suggest areas where leaders could direct more attention in order to increase the likelihood that EBIs are institutionalized into the normal functioning of the organization.

Senator Doug Jones (D-AL) Tour of MSFC Facilities

NASA Image and Video Library

2018-02-22

Senator Doug Jones (D-AL.) and wife, Louise, tour Marshall Space Flight facilities. Steve Doering, manager, Stages Element, Space Launch System (SLS) program at MSFC, views the test stand 4693 where key SLS structural elements will be subjected to stress testing simulating space flight.

Senator Doug Jones (D-AL) Tour of MSFC Facilities

NASA Image and Video Library

2018-02-22

Senator Doug Jones (D-AL.) and wife, Louise, tour Marshall Space Flight facilities. Steve Doering, manager, Stages Element, Space Launch System (SLS) program at MSFC, explains the stages of the SLS rocket with the scale model rocket located in the lobby of building 4200.

Tandem repeated application of organic solvents and sodium lauryl sulphate enhances cumulative skin irritation.

PubMed

Schliemann, Sibylle; Schmidt, Christina; Elsner, Peter

2014-01-01

The objective of our study was to investigate the tandem irritation potential of two organic solvents with concurrent exposure to the hydrophilic detergent irritant sodium lauryl sulphate (SLS). A tandem repeated irritation test was performed with two undiluted organic solvents, cumene (C) and octane (O), with either alternating application with SLS 0.5% or twice daily application of each irritant alone in 27 volunteers on the skin of the back. The cumulative irritation induced over 4 days was quantified using visual scoring and non-invasive bioengineering measurements (skin colour reflectance, skin hydration and transepidermal water loss). Repeated application of C/SLS and O/SLS induced more decline of stratum corneum hydration and higher degrees of clinical irritation and erythema compared to each irritant alone. Our results demonstrate a further example of additive harmful skin effects induced by particular skin irritants and indicate that exposure to organic solvents together with detergents may increase the risk of acquiring occupational contact dermatitis. © 2014 S. Karger AG, Basel.

Detecting Levels of Polyquaternium-10 (PQ-10) via Potentiometric Titration with Dextran Sulphate and Monitoring the Equivalence Point with a Polymeric Membrane-Based Polyion Sensor.

PubMed

Ferguson, Stephen A; Wang, Xuewei; Meyerhoff, Mark E

2016-08-07

Polymeric quaternary ammonium salts (polyquaterniums) have found increasing use in industrial and cosmetic applications in recent years. More specifically, polyquaternium-10 (PQ-10) is routinely used in cosmetic applications as a conditioner in personal care product formulations. Herein, we demonstrate the use of potentiometric polyion-sensitive polymeric membrane-based electrodes to quantify PQ-10 levels. Mixtures containing both PQ-10 and sodium lauryl sulfate (SLS) are used as model samples to illustrate this new method. SLS is often present in cosmetic samples that contain PQ-10 (e.g., shampoos, etc.) and this surfactant species interferes with the polyion sensor detection chemistry. However, it is shown here that SLS can be readily separated from the PQ-10/SLS mixture by use of an anion-exchange resin and that the PQ-10 can then be titrated with dextran sulphate (DS). This titration is monitored by potentiometric polyanion sensors to provide equivalence points that are directly proportional to PQ-10 concentrations.

Application of Sodium Ligno Sulphonate as Surfactant in Enhanced Oil Recovery and Its Feasibility Test for TPN 008 Oil

NASA Astrophysics Data System (ADS)

Prakoso, N. I.; Rochmadi; Purwono, S.

2018-04-01

One of enhanced oil recovery (EOR) methods is using surfactants to reduce the interfacial tension between the injected fluid and the oil in old reservoir. The most important principle in enhanced oil recovery process is the dynamic interaction of surfactants with crude oil. Sodium ligno sulphonate (SLS) is a commercial surfactant and already synthesized from palm solid waste by another researcher. This work aimed to apply SLS as a surfactant for EOR especially in TPN 008 oil from Pertamina Indonesia. In its application as an EOR’s surfactant, SLS shall be passed feasibility test like IFT, thermal stability, compatibility, filtration, molecular weight, density, viscosity and pH tests. The feasibility test is very important for a preliminary test prior to another advanced test. The results demonstrated that 1% SLS solution in formation water (TPN 008) had 0.254 mN/M IFT value and was also great in thermal stability, compatibility, filtration, molecular weight, viscosity and pH test.

Characteristics of the soil-like substrates produced with a novel technique combining aerobic fermentation and earthworm treatment

NASA Astrophysics Data System (ADS)

Kang, Wenli; He, Wenting; Li, Leyuan; Liu, Hong

2012-12-01

The soil-like substrate (SLS) technique is key for improving the closure of bioregenerative life support system (BLSS) by recycling the inedible biomass of higher plants. In this study, a novel SLS technique (NSLST) was proposed: aerobic fermentations at 35 °C for 1 day, then 60 °C for 6 days, finally 30 °C for 3 days, followed by earthworm treatment for 70 days. Comparing with the original SLS technique (OSLST), its process cycle was 13 days shorter, and the dry weight loss rate (81.1%) was improved by 24.77%. The cellulose and lignin degradation rates were 96.6% and 94.6%. The concentrations of available N, P and K in mature SLS were respectively 776.1 mg/L, 348.0 mg/L and 7943.0 mg/L. Low CH4 and NH3 production was observed, but no accumulation. According to the seed germination test, the SLSs were feasible for plant growth. This investigation will provide a preliminary foundation for BLSS design.

KSC-04PD-0007

NASA Technical Reports Server (NTRS)

2004-01-01

KENNEDY SPACE CENTER, FLA. -- In the Space Life Sciences (SLS) Lab, Jan Bauer, with Dynamac Corp., places samples of onion tissue in the elemental analyzer, which analyzes for carbon, hydrogen, nitrogen and sulfur. The 100,000 square-foot SLS houses labs for NASAs ongoing research efforts, microbiology/microbial ecology studies and analytical chemistry labs. Also calling the new lab home are facilities for space flight-experiment and flight-hardware development, new plant growth chambers, and an Orbiter Environment Simulator that will be used to conduct ground control experiments in simulated flight conditions for space flight experiments. The SLS Lab, formerly known as the Space Experiment Research and Processing Laboratory or SERPL, provides space for NASAs Life Sciences Services contractor Dynamac Corporation, Bionetics Corporation, and researchers from the University of Florida. NASAs Office of Biological and Physical Research will use the facility for processing life sciences experiments that will be conducted on the International Space Station. The SLS Lab is the magnet facility for the International Space Research Park at KSC being developed in partnership with Florida Space Authority.

2SLS versus 2SRI: Appropriate methods for rare outcomes and/or rare exposures.

PubMed

Basu, Anirban; Coe, Norma B; Chapman, Cole G

2018-06-01

This study used Monte Carlo simulations to examine the ability of the two-stage least squares (2SLS) estimator and two-stage residual inclusion (2SRI) estimators with varying forms of residuals to estimate the local average and population average treatment effect parameters in models with binary outcome, endogenous binary treatment, and single binary instrument. The rarity of the outcome and the treatment was varied across simulation scenarios. Results showed that 2SLS generated consistent estimates of the local average treatment effects (LATE) and biased estimates of the average treatment effects (ATE) across all scenarios. 2SRI approaches, in general, produced biased estimates of both LATE and ATE under all scenarios. 2SRI using generalized residuals minimized the bias in ATE estimates. Use of 2SLS and 2SRI is illustrated in an empirical application estimating the effects of long-term care insurance on a variety of binary health care utilization outcomes among the near-elderly using the Health and Retirement Study. Copyright © 2018 John Wiley & Sons, Ltd.

SLS Resource Reel Aug 2016 orig

NASA Image and Video Library

2016-07-04

Space Launch System Resource Reel Description: This video includes launch animation of NASA’s Space Launch System (SLS), as well as work taking place across NASA centers and the country to build and test the various components that make up the rocket including: the 5-segment solid rocket boosters, the RS-25 rocket engines, the massive tanks that make up the Core Stage of the rocket that fuels the RS-25 engines, and upper portions of the rocket that connect the interim cryogenic propulsion stage to the Orion spacecraft. SLS, is an advanced launch vehicle for a new era of exploration beyond Earth’s orbit into deep space. SLS, the world’s most powerful rocket, will launch astronauts in the agency’s Orion spacecraft on missions to an asteroid and eventually to Mars, while opening new possibilities for other payloads including robotic scientific missions to places like Mars, Saturn and Jupiter. Graphic Information: PAO Name:Kim Henry Phone Number:256-544-1899 Email Address: kimberly.m.henry@nasa.gov

Selective Laser Sintering of Porous Silica Enabled by Carbon Additive.

PubMed

Chang, Shuai; Li, Liqun; Lu, Li; Fuh, Jerry Ying Hsi

2017-11-16

The aim of this study is to investigate the possibility of a freeform fabrication of porous ceramic parts through selective laser sintering (SLS). SLS was proposed to manufacture ceramic green parts because this additive manufacturing technique can be used to fabricate three-dimensional objects directly without a mold, and the technique has the capability of generating porous ceramics with controlled porosity. However, ceramic printing has not yet fully achieved its 3D fabrication capabilities without using polymer binder. Except for the limitations of high melting point, brittleness, and low thermal shock resistance from ceramic material properties, the key obstacle lies in the very poor absorptivity of oxide ceramics to fiber laser, which is widely installed in commercial SLS equipment. An alternative solution to overcome the poor laser absorptivity via improving material compositions is presented in this study. The positive effect of carbon additive on the absorptivity of silica powder to fiber laser is discussed. To investigate the capabilities of the SLS process, 3D porous silica structures were successfully prepared and characterized.

NASA's Space Launch System: An Evolving Capability for Exploration

NASA Technical Reports Server (NTRS)

Creech, Stephen D.; Robinson, Kimberly F.

2016-01-01

Designed to meet the stringent requirements of human exploration missions into deep space and to Mars, NASA's Space Launch System (SLS) vehicle represents a unique new launch capability opening new opportunities for mission design. NASA is working to identify new ways to use SLS to enable new missions or mission profiles. In its initial Block 1 configuration, capable of launching 70 metric tons (t) to low Earth orbit (LEO), SLS is capable of not only propelling the Orion crew vehicle into cislunar space, but also delivering small satellites to deep space destinations. The evolved configurations of SLS, including both the 105 t Block 1B and the 130 t Block 2, offer opportunities for launching co-manifested payloads and a new class of secondary payloads with the Orion crew vehicle, and also offer the capability to carry 8.4- or 10-m payload fairings, larger than any contemporary launch vehicle, delivering unmatched mass-lift capability, payload volume, and C3.

Regulation of Strigolactone Biosynthesis by Gibberellin Signaling.

PubMed

Ito, Shinsaku; Yamagami, Daichi; Umehara, Mikihisa; Hanada, Atsushi; Yoshida, Satoko; Sasaki, Yasuyuki; Yajima, Shunsuke; Kyozuka, Junko; Ueguchi-Tanaka, Miyako; Matsuoka, Makoto; Shirasu, Ken; Yamaguchi, Shinjiro; Asami, Tadao

2017-06-01

Strigolactones (SLs) are a class of plant hormones that regulate diverse physiological processes, including shoot branching and root development. They also act as rhizosphere signaling molecules to stimulate the germination of root parasitic weeds and the branching of arbuscular mycorrhizal fungi. Although various types of cross talk between SLs and other hormones have been reported in physiological analyses, the cross talk between gibberellin (GA) and SLs is poorly understood. We screened for chemicals that regulate the level of SLs in rice ( Oryza sativa ) and identified GA as, to our knowledge, a novel SL-regulating molecule. The regulation of SL biosynthesis by GA is dependent on the GA receptor GID1 and F-box protein GID2. GA treatment also reduced the infection of rice plants by the parasitic plant witchers weed ( Striga hermonthica ). These data not only demonstrate, to our knowledge, the novel plant hormone cross talk between SL and GA, but also suggest that GA can be used to control parasitic weed infections. © 2017 American Society of Plant Biologists. All Rights Reserved.

Regulation of Strigolactone Biosynthesis by Gibberellin Signaling1[OPEN

PubMed Central

Ito, Shinsaku; Yamagami, Daichi; Umehara, Mikihisa; Hanada, Atsushi; Sasaki, Yasuyuki; Yajima, Shunsuke; Kyozuka, Junko; Ueguchi-Tanaka, Miyako; Matsuoka, Makoto; Yamaguchi, Shinjiro

2017-01-01

Strigolactones (SLs) are a class of plant hormones that regulate diverse physiological processes, including shoot branching and root development. They also act as rhizosphere signaling molecules to stimulate the germination of root parasitic weeds and the branching of arbuscular mycorrhizal fungi. Although various types of cross talk between SLs and other hormones have been reported in physiological analyses, the cross talk between gibberellin (GA) and SLs is poorly understood. We screened for chemicals that regulate the level of SLs in rice (Oryza sativa) and identified GA as, to our knowledge, a novel SL-regulating molecule. The regulation of SL biosynthesis by GA is dependent on the GA receptor GID1 and F-box protein GID2. GA treatment also reduced the infection of rice plants by the parasitic plant witchers weed (Striga hermonthica). These data not only demonstrate, to our knowledge, the novel plant hormone cross talk between SL and GA, but also suggest that GA can be used to control parasitic weed infections. PMID:28404726

Recent Research Trends on the Enzymatic Synthesis of Structured Lipids.

PubMed

Kim, Byung Hee; Akoh, Casimir C

2015-08-01

Structured lipids (SLs) are lipids that have been chemically or enzymatically modified from their natural biosynthetic form. Because SLs are made to possess desired nutritional, physicochemical, or textural properties for various applications in the food industry, many research activities have been aimed at their commercialization. The production of SLs by enzymatic procedures has a great potential in the future market because of the specificity of lipases and phospholipases used as the biocatalysts. The aim of this review is to provide concise information on the recent research trends on the enzymatic synthesis of SLs of commercial interest, such as medium- and long-chain triacylglycerols, human milk fat substitutes, cocoa butter equivalents, trans-free or low-trans plastic fats (such as margarines and shortenings), low-calorie fats/oils, health-beneficial fatty acid-rich fats/oils, mono- or diacylglycerols, and structurally modified phospholipids. This limited review covers 108 research articles published between 2010 and 2014 which were searched in Web of Science. © 2015 Institute of Food Technologists®

Enzymatic Synthesis of Refined Olive Oil-Based Structured Lipid Containing Omega -3 and -6 Fatty Acids for Potential Application in Infant Formula.

PubMed

Li, Ruoyu; Sabir, Jamal S M; Baeshen, Nabih A; Akoh, Casimir C

2015-11-01

Structured lipids (SLs) containing palmitic, docosahexaenoic (DHA), and gamma-linolenic (GLA) acids were produced using refined olive oil, tripalmitin, and ethyl esters of DHA single cell oil and GLA ethyl esters. Immobilized Lipozyme TL IM lipase was used as the biocatalyst. The SLs were characterized for fatty acid profile, triacylglycerol (TAG) molecular species, solid fat content, oxidative stability index, and melting and crystallization profiles and compared to physical blend of substrates, extracted fat from commercial infant formula (IFF), and milk fat. 49.28 mol% of palmitic acid was found at the sn-2 position of SL TAG and total DHA and GLA composition were 0.73 and 5.00 mol%, respectively. The total oleic acid content was 36.13 mol% which was very close to the 30.49% present in commercial IFF. Comparable solid fat content profiles were also found between SLs and IFF. The SLs produced have potential for use in infant formulas. © 2015 Institute of Food Technologists®

Automation of Flight Software Regression Testing

NASA Technical Reports Server (NTRS)

Tashakkor, Scott B.

2016-01-01

NASA is developing the Space Launch System (SLS) to be a heavy lift launch vehicle supporting human and scientific exploration beyond earth orbit. SLS will have a common core stage, an upper stage, and different permutations of boosters and fairings to perform various crewed or cargo missions. Marshall Space Flight Center (MSFC) is writing the Flight Software (FSW) that will operate the SLS launch vehicle. The FSW is developed in an incremental manner based on "Agile" software techniques. As the FSW is incrementally developed, testing the functionality of the code needs to be performed continually to ensure that the integrity of the software is maintained. Manually testing the functionality on an ever-growing set of requirements and features is not an efficient solution and therefore needs to be done automatically to ensure testing is comprehensive. To support test automation, a framework for a regression test harness has been developed and used on SLS FSW. The test harness provides a modular design approach that can compile or read in the required information specified by the developer of the test. The modularity provides independence between groups of tests and the ability to add and remove tests without disturbing others. This provides the SLS FSW team a time saving feature that is essential to meeting SLS Program technical and programmatic requirements. During development of SLS FSW, this technique has proved to be a useful tool to ensure all requirements have been tested, and that desired functionality is maintained, as changes occur. It also provides a mechanism for developers to check functionality of the code that they have developed. With this system, automation of regression testing is accomplished through a scheduling tool and/or commit hooks. Key advantages of this test harness capability includes execution support for multiple independent test cases, the ability for developers to specify precisely what they are testing and how, the ability to add automation, and the ability of the harness and cases to be executed continually. This test concept is an approach that can be adapted to support other projects.

Synthesis of Biomass and Utilization of Plant Wastes in a Physical Model of a Biological Life Support System

NASA Astrophysics Data System (ADS)

Tikhomirov, A. A.; Ushakova, S. A.; Manukovsky, N. S.; Lisovsky, G. M.; Kudenko, Yu A.; Kovalev, V. S.; Gribovksaya, I. V.; Tirranen, L. S.; Zolotukkhin, I. G.; Gros, J. B.; Lasseur, Ch.

Biological life support systems (LSS) with highly closed intrasystem mass ex change mass ex change hold much promise for long-term human life support at planetary stations (Moon, Mars, etc.). The paper considers problems of biosynthesis of higher plants' biomass and "biological incineration" of plant wastes in a working physical model of biological LSS. The plant wastes are "biologically incinerated" in a special heterotroph block involving Californian worms, mushrooms and straw. The block processes plant wastes (straw, haulms) to produce soil-like substrate (SLS) on which plants (wheat, radish) are grown. Gas ex change in such a system consists of respiratory gas ex change of SLS and photosynthesis and respiration of plants. Specifics of gas ex change dynamics of high plants -SLS complex has been considered. Relationship between such a gas ex change and photosynthetic active radiation (PAR) and age of plants has been established. SLS fertility has been shown to depend on its thickness and phase of maturity. The biogenic elements (potassium, phosphorus, nitrogen) in Liebig minimum have been found to include nitrogen which is the first to impair plants' growth in disruption of the process conditions. The SLS microflora has been found to have different kinds of ammonifying and denitrifying bacteria which is indicative of intensive transformation of nitrogen-containing compounds. The number of physiological groups of microorganisms in SLS was, on the whole, steady. As a result, organic substances -products of ex change of plants and microorganisms were not accumulated in the medium, but mineralized and assimilated by the biocenosis. Experiments showed that the developed model of a man-made ecosystem realized complete utilization of plant wastes and involved them into the intrasystem turnover. In multiple recycle of the mat ter (more than 5 cycles) under the irradiance intensity of 150 W/m2 PAR and the SLS mass (dry weight) of 17.7 -19.9 kg/m2 average total harvest of the plant mass was 2.14 kg/m2, the seed harvest was 0.85 kg/m2 (dry weight). The paper considers opportunities of using the technologies considered in biological LSS with long-term human presence.

Protein–Protein Interactions in Dilute to Concentrated Solutions: α-Chymotrypsinogen in Acidic Conditions

PubMed Central

2015-01-01

Protein–protein interactions were investigated for α-chymotrypsinogen by static and dynamic light scattering (SLS and DLS, respectively), as well as small-angle neutron scattering (SANS), as a function of protein and salt concentration at acidic conditions. Net protein–protein interactions were probed via the Kirkwood–Buff integral G22 and the static structure factor S(q) from SLS and SANS data. G22 was obtained by regressing the Rayleigh ratio versus protein concentration with a local Taylor series approach, which does not require one to assume the underlying form or nature of intermolecular interactions. In addition, G22 and S(q) were further analyzed by traditional methods involving fits to effective interaction potentials. Although the fitted model parameters were not always physically realistic, the numerical values for G22 and S(q → 0) were in good agreement from SLS and SANS as a function of protein concentration. In the dilute regime, fitted G22 values agreed with those obtained via the osmotic second virial coefficient B22 and showed that electrostatic interactions are the dominant contribution for colloidal interactions in α-chymotrypsinogen solutions. However, as protein concentration increases, the strength of protein–protein interactions decreases, with a more pronounced decrease at low salt concentrations. The results are consistent with an effective “crowding” or excluded volume contribution to G22 due to the long-ranged electrostatic repulsions that are prominent even at the moderate range of protein concentrations used here (<40 g/L). These apparent crowding effects were confirmed and quantified by assessing the hydrodynamic factor H(q → 0), which is obtained by combining measurements of the collective diffusion coefficient from DLS data with measurements of S(q → 0). H(q → 0) was significantly less than that for a corresponding hard-sphere system and showed that hydrodynamic nonidealities can lead to qualitatively incorrect conclusions regarding B22, G22, and static protein–protein interactions if one uses only DLS to assess protein interactions. PMID:24810917

Advanced Life Support Project: Crop Experiments at Kennedy Space Center

NASA Technical Reports Server (NTRS)

Sager, John C.; Stutte, Gary W.; Wheeler, Raymond M.; Yorio, Neil

2004-01-01

Crop production systems provide bioregenerative technologies to complement human crew life support requirements on long duration space missions. Kennedy Space Center has lead NASA's research on crop production systems that produce high value fresh foods, provide atmospheric regeneration, and perform water processing. As the emphasis on early missions to Mars has developed, our research focused on modular, scalable systems for transit missions, which can be developed into larger autonomous, bioregenerative systems for subsequent surface missions. Components of these scalable systems will include development of efficient light generating or collecting technologies, low mass plant growth chambers, and capability to operate in the high energy background radiation and reduced atmospheric pressures of space. These systems will be integrated with air, water, and thermal subsystems in an operational system. Extensive crop testing has been done for both staple and salad crops, but limited data is available on specific cultivar selection and breadboard testing to meet nominal Mars mission profiles of a 500-600 day surface mission. The recent research emphasis at Kennedy Space Center has shifted from staple crops, such as wheat, soybean and rice, toward short cycle salad crops such as lettuce, onion, radish, tomato, pepper, and strawberry. This paper will review the results of crop experiments to support the Exploration Initiative and the ongoing development of supporting technologies, and give an overview of capabilities of the newly opened Space Life Science (SLS) Lab at Kennedy Space Center. The 9662 square m (104,000 square ft) SLS Lab was built by the State of Florida and supports all NASA research that had been performed in Hanger-L. In addition to NASA research, the SLS Lab houses the Florida Space Research Institute (FSRI), responsible for co-managing the facility, and the University of Florida (UF) has established the Space Agriculture and Biotechnology Research and Education (SABRE) Center with several faculty.

Growth of plant tissue cultures in simulated lunar soil: Implications for a lunar base Controlled Ecological Life Support System (CELSS)

NASA Technical Reports Server (NTRS)

Venketeswaran, S.

1987-01-01

Experiments to determine whether plant tissue cultures can be grown in the presence of simulated lunar soil (SLS) and the effect of simulated lunar soil on the growth and morphogenesis of such cultures, as well as the effect upon the germination of seeds and the development of seedlings were carried out . Preliminary results on seed germination and seedling growth of rice and calli growth of winged bean and soybean indicate that there is no toxicity or inhibition caused by SLS. SLS can be used as a support medium with supplements of certain major and micro elements.

SRB Processing Facilities Media Event

NASA Image and Video Library

2016-03-01

Inside the Booster Fabrication Facility (BFF) at NASA’s Kennedy Space Center in Florida, members of the news media photograph a frustrum that will be stacked atop a forward skirt for one of NASA’s Space Launch System (SLS) solid rocket boosters. Orbital ATK is a contractor for NASA’s Marshall Space Flight Center in Alabama, and operates the BFF to prepare aft booster segments and hardware for the SLS solid rocket boosters. The SLS rocket and Orion spacecraft will launch on Exploration Mission-1 in 2018. The Ground Systems Development and Operations Program is preparing the infrastructure to process and launch spacecraft on deep-space missions and the journey to Mars.

Orion Stage Adapter (OSA) Offload

NASA Image and Video Library

2018-04-04

NASA Kennedy Space Center security officers prepare to escort the Orion Stage Adapter (OSA), secured on a flatbed transporter, along State Road 3 to the Space Station Processing Facility (SSPF) at NASA's Kennedy Space Center in Florida. The OSA is the second flight-hardware section of the agency's Space Launch System (SLS) rocket to arrive at Kennedy. The OSA will connect the Orion spacecraft to the upper part of the SLS, the interim cryogenic propulsion stage (ICPS). Both the OSA and ICPS are being stored for processing in the SSPF in preparation for Exploration Mission-1, the first uncrewed, integrated launch of the SLS rocket and Orion spacecraft.

Update on Risk Reduction Activities for a Liquid Advanced Booster for NASA's Space Launch System

NASA Technical Reports Server (NTRS)

Crocker, Andy; Greene, William D.

2017-01-01

Goals of NASA's Advanced Booster Engineering Demonstration and/or Risk Reduction (ABEDRR) are to: (1) Reduce risks leading to an affordable Advanced Booster that meets the evolved capabilities of SLS. (2) Enable competition by mitigating targeted Advanced Booster risks to enhance SLS affordability. SLS Block 1 vehicle is being designed to carry 70 mT to LEO: (1) Uses two five-segment solid rocket boosters (SRBs) similar to the boosters that helped power the space shuttle to orbit. Evolved 130 mT payload class rocket requires an advanced booster with more thrust than any existing U.S. liquid-or solid-fueled boosters

Platform C North Arrival

NASA Image and Video Library

2016-08-30

A section of the second half of the C-level platforms, C North, for NASA’s Space Launch System (SLS) rocket, arrives at the agency’s Kennedy Space Center in Florida. The platform was offloaded from a heavy lift transport truck and secured in a staging area in the west parking lot of the Vehicle Assembly Building (VAB). The Ground Systems Development and Operations Program is overseeing upgrades and modifications to VAB High Bay 3 to support processing of the SLS and Orion spacecraft. A total of 10 levels of new platforms, 20 platform halves altogether, will surround the SLS rocket and Orion spacecraft and provide access for testing and processing.

ROBERT BOBO AND MIKE NICHOLS AT TEST STAND 4693

NASA Image and Video Library

2016-12-14

ROBERT BOBO, LEFT, AND MIKE NICHOLS TALK BENEATH THE 221-FOOT-TALL TEST STAND 4693, THE LARGEST OF TWO NEW SPACE LAUNCH SYSTEM TEST STANDS AT MSFC. BOBO MANAGES SLS STRUCTURAL STRENGTH TESTING, AND NICHOLS IS LEAD TEST ENGINEER FOR THE SLS LIQUID HYDROGEN TANK.

SLS INTERTANK TEST ARTICLE IS ATTACHED TO CROSSHEAD OF LOAD TEST ANNEX, BLDG. 4619, AND REMOVED FROM BED OF KMAG TRANSPORTER

NASA Image and Video Library

2018-03-28

SLS INTERTANK TEST ARTICLE IS ATTACHED TO CROSSHEAD OF LOAD TEST ANNEX, BLDG. 4619, AND REMOVED FROM BED OF KMAG TRANSPORTER. Matt Cash conducts tag up meeting before lift of ITA from KMAG transporter

SLS Intertank Test Article, ITA, is attached to crosshead of loa

NASA Image and Video Library

2018-04-04

SLS Intertank Test Article, ITA, is attached to crosshead of load test Annex, Bldg. 4619, and removed from bed of KMAG transporter. Rob Ziegler, L, and Roger Myrick, R, of Aerie Aerospace attach load lines to Aft Load Ring of Intertank Test Articlle

The SLS Stages Intertank Structural Test Assembly (STA) arrives at MSFC

NASA Image and Video Library

2018-03-06

The SLS Stages Intertank Structural Test Assembly (STA) is rolling off the NASA Pegasus Barge at the MSFC Dock enroute to the MSFC 4619 Load Test Annex test facility for qualification testing. STA hardware completely free of barge and flanked by tug boats.

SLS Intertank Test Article, ITA, is attached to crosshead of loa

NASA Image and Video Library

2018-04-04

SLS Intertank Test Article, ITA, is attached to crosshead of load test Annex, Bldg. 4619, and removed from bed of KMAG transporter. Rob Ziegler, (L), and Roger Myrick (R), of Aerie Aerospace attach load lines to Aft Load Ring of Intertank Test Article.

NASA on a Strong Roll in Preparing Space Launch System Flight Engines

NASA Image and Video Library

2017-08-09

NASA is on a roll when it comes to testing engines for its new Space Launch System (SLS) rocket that will send astronauts to deep-space destinations, including Mars. Just two weeks after the third test of a new RS-25 engine flight controller, the space agency recorded its fourth full-duration controller test Aug. 9 at Stennis Space Center near Bay St. Louis, Mississippi. Engineers conducted a 500-second test of the RS-25 engine controller on the A-1 Test Stand at Stennis. The test involved installing the controller on an RS-25 development engine and firing it in the same manner, and for the same length of time, as needed during an actual SLS launch. The test marked another milestone toward launch of the first integrated flight of the SLS rocket and Orion crew vehicle. Exploration Mission-1 will be an uncrewed mission into lunar orbit, designed to provide a final check-out test of rocket and Orion capabilities before astronauts are returned to deep space. The SLS rocket will be powered at launch by four RS-25 engines, providing a combined 2 million pounds of thrust, and with a pair of solid rocket boosters, providing more than 8 million pounds of total thrust. The RS-25 engines for the initial SLS flights are former space shuttle main engines that are now being used to launch the larger and heavier SLS rocket and with the new controller. The controller is a critical component that operates as the engine “brain” that communicates with SLS flight computers to receive operation performance commands and to provide diagnostic data on engine health and status. Engineers conducted early prototype tests at Stennis to collect data for development of the new controller by NASA, RS-25 prime contractor Aerojet Rocketdyne and subcontractor Honeywell. Testing of actual flight controllers began at Stennis in March. NASA is testing all controllers and engines designated for the EM-1 flight at Stennis. It also will test the SLS core stage for the flight at Stennis, which will involve installing the stage on the B-2 Test Stand and firing its four RS-25 engines simultaneously, as during an actual launch. RS-25 tests at Stennis are conducted by a team of NASA, Aerojet Rocketdyne and Syncom Space Services engineers and operators. Aerojet Rocketdyne is the RS-25 prime contractor. Syncom Space Services is the prime contractor for Stennis facilities and operations.

Skin barrier disruption by sodium lauryl sulfate-exposure alters the expressions of involucrin, transglutaminase 1, profilaggrin, and kallikreins during the repair phase in human skin in vivo.

PubMed

Törmä, Hans; Lindberg, Magnus; Berne, Berit

2008-05-01

Detergents are skin irritants affecting keratinocytes. In this study, healthy volunteers were exposed to water (vehicle) and 1% sodium lauryl sulfate (SLS) under occlusive patch tests for 24 hours. The messenger RNA (mRNA) expression of keratinocyte differentiation markers and of enzymes involved in corneodesmosome degradation was examined in skin biopsies (n=8) during the repair phase (6 hours to 7 days postexposure) using real-time reverse-transcription PCR. It was found that the expression of involucrin was increased at 6 hours, but then rapidly normalized. The expression of transglutaminase 1 exhibited a twofold increase after 24 hours in the SLS-exposed skin. Profilaggrin was decreased after 6 hours. Later (4-7 days), the expression in SLS-exposed areas was >50% above than in control areas. An increased and altered immunofluorescence pattern of involucrin, transglutaminase 1, and filaggrin was also found (n=4). At 6 hours post-SLS exposure, the mRNA expression of kallikrein-7 (KLK-7) and kallikrein-5 (KLK-5) was decreased by 50 and 75%, respectively, as compared with control and water-exposed areas. Thereafter, the expression pattern of KLK-7 and KLK-5 was normalized. Changes in protein expression of KLK-5 were also found. In conclusion, SLS-induced skin barrier defects induce altered mRNA expression of keratinocyte differentiation markers and enzymes degrading corneodesmosomes.

Skin deposition and permeation of finasteride in vitro: effects of propylene glycol, ethanol and sodium lauryl sulfate.

PubMed

Limpongsa, Ekapol; Jaipakdee, Napaphak; Pongjanyakul, Thaned

2014-08-27

Abstract The objective of this study was to investigate the effects of propylene glycol (PG), ethanol (EtOH) and sodium lauryl sulfate (SLS) on the in vitro deposition and permeation of finasteride (FNS). A side-by-side diffusion cell mounted with a pig ear skin and a saturated solution of FNS in PG (10, 20% v/v), EtOH (10, 20% v/v) or SLS (0.5, 1% w/v) vehicles were used. Incorporation of PG, EtOH or SLS caused a significant increase in FNS solubility both in the solution and on the skin with SLS > EtOH > PG. The results obtained from skin deposition studies showed that the FNS deposition rate and time increased in the same order as that of the solubility. The deposition kinetics of FNS solubilized in PG, EtOH and SLS vehicles followed either zero-order, square-root-of-time or pseudo-first-order kinetic models depending on the type and concentration of the enhancer. The permeation studies demonstrated that FNS permeation fluxes were enhanced only by EtOH vehicles. These results suggest that PG and SLS could be used as deposition enhancers, while EtOH could be the effective permeation enhancer of FNS. The obtained results can be used as the considerable insights for formulating the topical and transdermal products of FNS.

Enhancing the transdermal delivery of rigid nanoparticles using the simultaneous application of ultrasound and sodium lauryl sulfate

PubMed Central

Lopez, Renata F.V.; Seto, Jennifer E.; Blankschtein, Daniel; Langer, Robert

2010-01-01

The potential of rigid nanoparticles to serve as transdermal drug carriers can be greatly enhanced by improving their skin penetration. Therefore, the simultaneous application of ultrasound and sodium lauryl sulfate (referred to as US/SLS) was evaluated as a skin pre-treatment method for enhancing the passive transdermal delivery of nanoparticles. We utilized inductively-coupled plasma mass spectrometry and an improved application of confocal microscopy to compare the delivery of 10- and 20-nm cationic, neutral, and anionic quantum dots (QDs) into US/SLS-treated and untreated pig split-thickness skin. Our findings include: (a) ~0.01% of the QDs penetrate the dermis of untreated skin (which we quantify for the first time), (b) the QDs fully permeate US/SLS-treated skin, (c) the two cationic QDs studied exhibit different extents of skin penetration and dermal clearance, and (d) the QD skin penetration is heterogeneous. We discuss routes of nanoparticle skin penetration and the application of the methods described herein to address conflicting literature reports on nanoparticle skin penetration. We conclude that US/SLS treatment significantly enhances QD transdermal penetration by 500–1300%. Our findings suggest that an optimum surface charge exists for nanoparticle skin penetration, and motivate the application of nanoparticle carriers to US/SLS-treated skin for enhanced transdermal drug delivery. PMID:20971504

Enhancing the transdermal delivery of rigid nanoparticles using the simultaneous application of ultrasound and sodium lauryl sulfate.

PubMed

Lopez, Renata F V; Seto, Jennifer E; Blankschtein, Daniel; Langer, Robert

2011-01-01

The potential of rigid nanoparticles to serve as transdermal drug carriers can be greatly enhanced by improving their skin penetration. Therefore, the simultaneous application of ultrasound and sodium lauryl sulfate (referred to as US/SLS) was evaluated as a skin pre-treatment method for enhancing the passive transdermal delivery of nanoparticles. We utilized inductively coupled plasma mass spectrometry and an improved application of confocal microscopy to compare the delivery of 10- and 20-nm cationic, neutral, and anionic quantum dots (QDs) into US/SLS-treated and untreated pig split-thickness skin. Our findings include: (a) ∼0.01% of the QDs penetrate the dermis of untreated skin (which we quantify for the first time), (b) the QDs fully permeate US/SLS-treated skin, (c) the two cationic QDs studied exhibit different extents of skin penetration and dermal clearance, and (d) the QD skin penetration is heterogeneous. We discuss routes of nanoparticle skin penetration and the application of the methods described herein to address conflicting literature reports on nanoparticle skin penetration. We conclude that US/SLS treatment significantly enhances QD transdermal penetration by 500-1300%. Our findings suggest that an optimum surface charge exists for nanoparticle skin penetration, and motivate the application of nanoparticle carriers to US/SLS-treated skin for enhanced transdermal drug delivery. Copyright © 2010 Elsevier Ltd. All rights reserved.

Radiometric characterization of an LWIR, type-II strained layer superlattice pBiBn photodetector

NASA Astrophysics Data System (ADS)

Treider, L. A.; Morath, C. P.; Cowan, V. M.; Tian, Z. B.; Krishna, S.

2015-05-01

Type-II Strained Layer Superlattice (T2SLS) infrared photodetectors have been in development over the last decade. T2SLS offers a theoretically longer Auger recombination lifetime than traditional mercury cadmium telluride (MCT), which presumably translates to infrared detectors with lower dark-current and higher operating temperatures. However, these improvements did not materialize due to the presence of Shockley-Read-Hall (SRH) defects in T2SLSs, which limits the recombination lifetime well below the Auger-limit. With the recent introduction of the pBiBn, and other similar unipolar barrier detectors, T2SLS material has seen renewed interest since these designs ideally eliminate the SRH-generation and surface currents while retaining the other potential advantages of T2SLS: reduced manufacturing cost, better availability of a durable state-side manufacturing base, ability to tune the cutoff wavelength, and better uniformity. Here, an electrical and optical characterization of a long-wave, pBiBn detector with a T2SLS absorber is presented. Dark-current, spectral response and optical response were measured as functions of temperature and bias. Activation energy was then determined as a function of bias from the dark-current measurements. Quantum efficiency was also determined as a function of bias from the optical response measurements. Additionally, noise spectrum measurements were taken as a function of bias.

Lower thermospheric-enhanced sodium layers observed at low latitude and possible formation: Case studies

NASA Astrophysics Data System (ADS)

Xue, X. H.; Dou, X. K.; Lei, J.; Chen, J. S.; Ding, Z. H.; Li, T.; Gao, Q.; Tang, W. W.; Cheng, X. W.; Wei, K.

2013-05-01

We report two lower thermospheric-enhanced sodium layer (TeSL) cases observed at a low-latitude station, Lijiang, China (26.7°N, 100.0°E), on 10 March and 10 April 2012, respectively. The TeSLs in the two cases were located at altitudes near 122 and 112 km, respectively. In addition, strong sporadic sodium layers (SSLs) near 100 km accompanied the TeSL observed on 10 March 2012. Both the TeSLs and SSLs exhibited tidal-induced downward motion. The adjacent ground-based and space-borne ionospheric radio observations showed strong Es layers before the appearance of the TeSLs, suggesting an " Es- TeSLs (SSLs)" chain formed through the tidal wind shear mechanism. Assuming that the vertical tidal wavelengths remain unchanged, it is found that in different regions caused by the tidal wind shear, different TeSLs evolution processes are expected: (1) in a tidal-convergence region, a TeSL/SSL with a downward propagation phase is enhanced due to a rapid decrease in the Na+lifetime at the lower altitude; (2) in an ion convergence-divergence interface region, a TeSL/SSL will still follow the tidal downward phase progression, but sodium density does not exhibit evident enhancement; and (3) when a TeSL/SSL enters into a tidal wind-divergence zone, the layer density tends to decrease.

Localization of 1-deoxysphingolipids to mitochondria induces mitochondrial dysfunction.

PubMed

Alecu, Irina; Tedeschi, Andrea; Behler, Natascha; Wunderling, Klaus; Lamberz, Christian; Lauterbach, Mario A R; Gaebler, Anne; Ernst, Daniela; Van Veldhoven, Paul P; Al-Amoudi, Ashraf; Latz, Eicke; Othman, Alaa; Kuerschner, Lars; Hornemann, Thorsten; Bradke, Frank; Thiele, Christoph; Penno, Anke

2017-01-01

1-Deoxysphingolipids (deoxySLs) are atypical sphingolipids that are elevated in the plasma of patients with type 2 diabetes and hereditary sensory and autonomic neuropathy type 1 (HSAN1). Clinically, diabetic neuropathy and HSAN1 are very similar, suggesting the involvement of deoxySLs in the pathology of both diseases. However, very little is known about the biology of these lipids and the underlying pathomechanism. We synthesized an alkyne analog of 1-deoxysphinganine (doxSA), the metabolic precursor of all deoxySLs, to trace the metabolism and localization of deoxySLs. Our results indicate that the metabolism of these lipids is restricted to only some lipid species and that they are not converted to canonical sphingolipids or fatty acids. Furthermore, exogenously added alkyne-doxSA [(2S,3R)-2-aminooctadec-17-yn-3-ol] localized to mitochondria, causing mitochondrial fragmentation and dysfunction. The induced mitochondrial toxicity was also shown for natural doxSA, but not for sphinganine, and was rescued by inhibition of ceramide synthase activity. Our findings therefore indicate that mitochondrial enrichment of an N-acylated doxSA metabolite may contribute to the neurotoxicity seen in diabetic neuropathy and HSAN1. Hence, we provide a potential explanation for the characteristic vulnerability of peripheral nerves to elevated levels of deoxySLs. Copyright © 2017 by the American Society for Biochemistry and Molecular Biology, Inc.

Bond and fracture strength of metal-ceramic restorations formed by selective laser sintering

PubMed Central

Bae, Eun-Jeong; Kim, Woong-Chul; Kim, Hae-Young

2014-01-01

PURPOSE The purpose of this study was to compare the fracture strength of the metal and the bond strength in metal-ceramic restorations produced by selective laser sintering (SLS) and by conventional casting (CAST). MATERIALS AND METHODS Non-precious alloy (StarLoy C, DeguDent, Hanau, Germany) was used in CAST group and metal powder (SP2, EOS GmbH, Munich, Germany) in SLS group. Metal specimens in the form of sheets (25.0 × 3.0 × 0.5 mm) were produced in accordance with ISO 9693:1999 standards (n=30). To measure the bond strength, ceramic was fired on a metal specimen and then three-point bending test was performed. In addition, the metal fracture strength was measured by continuing the application of the load. The values were statistically analyzed by performing independent t-tests (α=.05). RESULTS The mean bond strength of the SLS group (50.60 MPa) was higher than that of the CAST group (46.29 MPa), but there was no statistically significant difference. The metal fracture strength of the SLS group (1087.2 MPa) was lower than that of the CAST group (2399.1 MPa), and this difference was statistically significant. CONCLUSION In conclusion the balling phenomenon and the gap formation of the SLS process may increase the metal-ceramic bond strength. PMID:25177469

Space Launch System Resource Reel 2017

NASA Image and Video Library

2017-12-01

NASA's new heavy-lift rocket, the Space Launch System, will be the most powerful rocket every built, launching astronauts in NASA's Orion spacecraft on missions into deep space. Two solid rocket boosters and four RS-25 engines will power the massive rocket, providing 8 million pounds of thrust during launch. Production and testing are underway for much of the rocket's critical hardware. With major welding complete on core stage hardware for the first integrated flight of SLS and Orion, the liquid hydrogen tank, intertank and liquid oxygen tank are ready for further outfitting. NASA's barge Pegasus has transported test hardware the first SLS hardware, the engine section to NASA's Marshall Space Flight Center in Huntsville, Alabama, for testing. In preparation for testing and handling operations, engineers have built the core stage pathfinder, to practice transport without the risk of damaging flight hardware. Integrated structural testing is complete on the top part of the rocket, including the Orion stage adapter, launch vehicle stage adapter and interim cryogenic propulsion stage. The Orion Stage Adapter for SLS's first flight, which will carry 13 CubeSats as secondary payloads, is ready to be outfitted with wiring and brackets. Once structural testing and flight hardware production are complete, the core stage will undergo "green run" testing in the B-2 test stand at NASA's Stennis Space Center in Bay St. Louis, Mississippi. For more information about SLS, visit nasa.gov/sls.

SLS INTERIM CRYOGENIC PROPULSION STAGE TEST ARTICLE ARRIVAL

NASA Image and Video Library

2016-06-19

SLS INTERIM CRYOGENIC PROPULSION STAGE TEST ARTICLE ARRIVES AT WEST DOCK ON SHIELDS ROAD AND IS OFF LOADED FROM BARGEUAH ENGINEERING STUDENT ROBERT HILLAN TALKS TO SPACE STATION CREW MEMBERS ABOUT HIS WINNING 3-D PRINTED TOOL DESIGNED FOR USE ON ISS, AND IS INTERVIEWED BY LOCAL MEDIA

Development of Processing Parameters for Organic Binders Using Selective Laser Sintering

NASA Technical Reports Server (NTRS)

Mobasher, Amir A.

2003-01-01

This document describes rapid prototyping, its relation to Computer Aided Design (CAD), and the application of these techniques to choosing parameters for Selective Laser Sintering (SLS). The document reviews the parameters selected by its author for his project, the SLS machine used, and its software.

High-titer production and strong antimicrobial activity of sophorolipids from Rhodotorula bogoriensis

USDA-ARS?s Scientific Manuscript database

Rhodotorula bogoriensis produces sophorolipids (SLs) that contain 13-hydroxydocosanoic acid (OH-C22) as the lipid moiety. A systematic study was conducted to further understand the fermentative production of SLs containing OH-C22 (C22-SL) by R. bogoriensis. Shake-flask studies showed that R. bogor...

Biopolymer scaffolds for use in delivering antimicrobial Sophorolipids to the acne-causing bacterium propionibacterium acnes

USDA-ARS?s Scientific Manuscript database

Sophorolipids (SLs) are known to possess antimicrobial properties towards many species (particularly Gram-positive, or Gram+) of bacteria. However, they can only be exerted if the SLs can be introduced to the bacterial cells in an acceptable manner. Propionibacterium acnes is the common bacterial ...

Space Launch System Spacecraft and Payload Elements: Progress Toward Crewed Launch and Beyond

NASA Technical Reports Server (NTRS)

Schorr, Andrew A.; Smith, David Alan; Holcomb, Shawn; Hitt, David

2017-01-01

While significant and substantial progress continues to be accomplished toward readying the Space Launch System (SLS) rocket for its first test flight, work is already underway on preparations for the second flight - using an upgraded version of the vehicle - and beyond. Designed to support human missions into deep space, SLS is the most powerful human-rated launch vehicle the United States has ever undertaken, and is one of three programs being managed by the National Aeronautics and Space Administration's (NASA's) Exploration Systems Development division. The Orion spacecraft program is developing a new crew vehicle that will support human missions beyond low Earth orbit (LEO), and the Ground Systems Development and Operations (GSDO) program is transforming Kennedy Space Center (KSC) into a next-generation spaceport capable of supporting not only SLS but also multiple commercial users. Together, these systems will support human exploration missions into the proving ground of cislunar space and ultimately to Mars. For its first flight, SLS will deliver a near-term heavy-lift capability for the nation with its 70-metric-ton (t) Block 1 configuration. Each element of the vehicle now has flight hardware in production in support of the initial flight of the SLS, which will propel Orion around the moon and back. Encompassing hardware qualification, structural testing to validate hardware compliance and analytical modeling, progress is on track to meet the initial targeted launch date. In Utah and Mississippi, booster and engine testing are verifying upgrades made to proven shuttle hardware. At Michoud Assembly Facility (MAF) in Louisiana, the world's largest spacecraft welding tool is producing tanks for the SLS core stage. Providing the Orion crew capsule/launch vehicle interface and in-space propulsion via a cryogenic upper stage, the Spacecraft/Payload Integration and Evolution (SPIE) element serves a key role in achieving SLS goals and objectives. The SPIE element marked a major milestone in 2014 with the first flight of original SLS hardware, the Orion Stage Adapter (OSA) which was used on Exploration Flight Test-1 with a design that will be used again on the first flight of SLS. The element has overseen production of the Interim Cryogenic Propulsion Stage (ICPS), an in-space stage derived from the Delta Cryogenic Second Stage, which was manufactured at United Launch Alliance (ULA) in Decatur, Alabama, prior to being shipped to Florida for flight preparations. Manufacture of the OSA and the Launch Vehicle Stage Adapter (LVSA) took place at the Friction Stir Facility located at Marshall Space Flight Center (MSFC) in Huntsville, Alabama. Marshall is also home to the Integrated Structural Test of the ICPS, LVSA, and OSA, subjecting the stacked components to simulated stresses of launch. The SPIE Element is also overseeing integration of 13 "CubeSat" secondary payloads that will fly on the first flight of SLS, providing access to deep space regions in a way currently not available to the science community. At the same time as this preparation work is taking place toward the first launch of SLS, however, the Space Launch System Program is actively working toward its second launch. For its second flight, SLS will be upgraded to the more-capable Block 1B configuration. While the Block 1 configuration is capable of delivering more than 70 t to LEO, the Block 1B vehicle will increase that capability to 105 t. For that flight, the new configuration introduces two major new elements to the vehicle - an Exploration Upper Stage (EUS) that will be used for both ascent and in-space propulsion, and a Universal Stage Adapter (USA) that serves as a "payload bay" for the rocket, allowing the launch of large exploration systems along with the Orion spacecraft. Already, flight hardware is being prepared for the Block 1B vehicle. Welding is taking place on the second rocket's core stage. Flight hardware production has begun on booster components. An RS-25 engine slated for that flight has been tested. Development work is taking place on the EUS, with contracts in place for both the stage and the RL10 engines which will power it. (The EUS will use four RL10 engines, an increase from one on the ICPS.) For the crew configuration of the Block 1B vehicle, the SLS SPIE element is managing the USA and accompanying Payload Adapter, which will accommodate both large payloads co-manifested with Orion and small-satellite secondary payloads. This co-manifested payload capacity will be instrumental for missions into the proving ground around the moon, where NASA will test new systems and demonstrate new capabilities needed for human exploration farther into deep space.

Space Launch System Spacecraft and Payload Elements: Progress Toward Crewed Launch and Beyond

NASA Technical Reports Server (NTRS)

Schorr, Andrew A.; Creech, Stephen D.

2017-01-01

While significant and substantial progress continues to be accomplished toward readying the Space Launch System (SLS) rocket for its first test flight, work is already also underway on preparations for the second flight - using an upgraded version of the vehicle - and beyond. Designed to support human missions into deep space, Space Launch System (SLS), is the most powerful human-rated launch vehicle the United States has ever undertaken, and is one of three programs being managed by the National Aeronautics and Space Administration's (NASA's) Exploration Systems Development division. The Orion spacecraft program is developing a new crew vehicle that will support human missions beyond low Earth orbit (LEO), and the Ground Systems Development and Operations program is transforming Kennedy Space Center into a next-generation spaceport capable of supporting not only SLS but also multiple commercial users. Together, these systems will support human exploration missions into the proving ground of cislunar space and ultimately to Mars. For its first flight, SLS will deliver a near-term heavy-lift capability for the nation with its 70-metric-ton (t) Block 1 configuration. Each element of the vehicle now has flight hardware in production in support of the initial flight of the SLS, which will propel Orion around the moon and back. Encompassing hardware qualification, structural testing to validate hardware compliance and analytical modeling, progress in on track to meet the initial targeted launch date. In Utah and Mississippi, booster and engine testing are verifying upgrades made to proven shuttle hardware. At Michoud Assembly Facility in Louisiana, the world's largest spacecraft welding tool is producing tanks for the SLS core stage. Providing the Orion crew capsule/launch vehicle interface and in-space propulsion via a cryogenic upper stage, the Spacecraft/Payload Integration and Evolution (SPIE) element serves a key role in achieving SLS goals and objectives. The SPIE element marked a major milestone in 2014 with the first flight of original SLS hardware, the Orion Stage Adapter (OSA) which was used on Exploration Flight Test-1 with a design that will be used again on the first flight of SLS. The element has overseen production of the Interim Cryogenic Propulsion Stage (ICPS), an in-space stage derived from the Delta Cryogenic Second Stage, which was manufactured at United Launch Alliance in Decatur, Alabama, prior to being shipped to Florida for flight preparations. Manufacture of the Orion Stage Adapter and the Launch Vehicle Stage Adapter (LVSA) took place at the Friction Stir Facility located at Marshall Space Flight Center in Huntsville, Alabama. Marshall is also home to the Integrated Structural Test of the ICPS, LVSA, and OSA, subjecting the stacked components to simulated stresses of launch. The SPIE Element is also overseeing integration of 13 "CubeSat" secondary payloads that will fly on the first flight of SLS, providing access to deep space regions in a way currently not available to the science community. At the same time as this preparation work is taking place toward the first launch of SLS, however, the Space Launch System Program is actively working toward its second launch. For its second flight, SLS will be upgraded to the more-capable Block 1B configuration. While the Block 1 configuration is capable of delivering more than 70 metric tons to low Earth orbit, the Block 1B vehicle will increase that capability to 105 t. For that flight, the new configuration introduces two major new elements to the vehicle - an Exploration Upper Stage (EUS) that will be used for both ascent and in-space propulsion, and a Universal Stage Adapter (USA) that serves as a "payload bay" for the rocket, allowing the launch of large exploration systems along with the Orion spacecraft. Already, flight hardware is being prepared for the Block 1B vehicle. Welding is taking place on the second rocket's core stage. Flight hardware production has begun on booster components. An RS-25 engine slated for that flight has been tested. Development work is taking place on the Exploration Upper Stage, with contracts in place for both the stage and the RL10 engines which will power it. (The EUS will use four RL10 engines, an increase from one on the ICPS.) For the crew configuration of the Block 1B vehicle, the SLS SPIE element is managing the USA and accompanying Payload Adapter, which will accommodate both large payloads co-manifested with Orion and small-satellite secondary payloads. This co-manifested payload capacity will be instrumental for missions into the Proving Ground around the moon, where NASA will test new systems and demonstrate new capabilities needed for human exploration farther into deep space.

Weak bases and formation of a less soluble lauryl sulfate salt/complex in sodium lauryl sulfate (SLS) containing media.

PubMed

Bhattachar, Shobha N; Risley, Donald S; Werawatganone, Pornpen; Aburub, Aktham

2011-06-30

This work reports on the solubility of two weakly basic model compounds in media containing sodium lauryl sulfate (SLS). Results clearly show that the presence of SLS in the media (e.g. simulated gastric fluid or dissolution media) can result in an underestimation of solubility of some weak bases. We systematically study this phenomenon and provide evidence (chromatography and pXRD) for the first time that the decrease in solubility is likely due to formation of a less soluble salt/complex between the protonated form of the weak base and lauryl sulfate anion. Copyright © 2011 Elsevier B.V. All rights reserved.

Vehicle Support Posts Installation onto Mobile Launcher

NASA Image and Video Library

2017-05-11

Four vehicle support posts have been installed on the deck of the mobile launcher at NASA's Kennedy Space Center in Florida. A total of eight support posts will be installed to support the load of the Space Launch System's (SLS) solid rocket boosters, with four posts for each of the boosters. The support posts are about five feet tall and each weigh about 10,000 pounds. The posts will structurally support the SLS rocket through T-0 and liftoff, and will drop down before vehicle liftoff to avoid contact with the flight hardware. The Ground Systems Development and Operations Program is overseeing installation of the support posts to prepare for the launch of the Orion spacecraft atop the SLS rocket.

NASA's Space Launch System: Systems Engineering Approach for Affordability and Mission Success

NASA Technical Reports Server (NTRS)

Hutt, John J.; Whitehead, Josh; Hanson, John

2017-01-01

NASA is working toward the first launch of the Space Launch System, a new, unmatched capability for deep space exploration with launch readiness planned for 2019. Since program start in 2011, SLS has passed several major formal design milestones, and every major element of the vehicle has produced test and flight hardware. The SLS approach to systems engineering has been key to the program's success. Key aspects of the SLS SE&I approach include: 1) minimizing the number of requirements, 2) elimination of explicit verification requirements, 3) use of certified models of subsystem capability in lieu of requirements when appropriate and 4) certification of capability beyond minimum required capability.

Tail Service Mast Umbilical Arrival

NASA Image and Video Library

2016-08-02

A heavy-lift transport truck arrives at the Launch Equipment Test Facility (LETF) at NASA’s Kennedy Space Center in Florida, with the first of two Tail Service Mast Umbilicals (TSMU) for NASA’s Space Launch System (SLS). Two TSMUs will provide liquid propellants and power to the Space Launch System (SLS) rocket’s core stage engine. Both TSMUs will connect to the zero-level deck on the mobile launcher, providing fuel and electricity to the SLS rocket before it launches on Exploration Mission 1. The TSMU will undergo testing and validation at the LETF to verify it is functioning properly. The center’s Engineering Directorate and the Ground Systems Development and Operations Program are overseeing processing and testing of the umbilicals.

Tail Service Mast Umbilical Arrival

NASA Image and Video Library

2016-08-02

A crane is prepared to help lift the first Tail Service Mast Umbilical (TSMU) for NASA’s Space Launch System (SLS) at the Launch Equipment Test Facility (LETF) at NASA’s Kennedy Space Center in Florida. Two TSMUs will provide liquid propellants and power to the Space Launch System (SLS) rocket’s core stage engine. Both TSMUs will connect to the zero-level deck on the mobile launcher, providing fuel and electricity to the SLS rocket before it launches on Exploration Mission 1. The TSMU will undergo testing and validation at the LETF to verify it is functioning properly. The center’s Engineering Directorate and the Ground Systems Development and Operations Program are overseeing processing and testing of the umbilicals.

Tail Service Mast Umbilical Arrival

NASA Image and Video Library

2016-08-02

A crane is attached to the first Tail Service Mast Umbilical (TSMU) for NASA’s Space Launch System (SLS) at the Launch Equipment Test Facility at NASA’s Kennedy Space Center in Florida. Two TSMUs will provide liquid propellants and power to the Space Launch System (SLS) rocket’s core stage engine. Both TSMUs will connect to the zero-level deck on the mobile launcher, providing fuel and electricity to the SLS rocket before it launches on Exploration Mission 1. The TSMU will undergo testing and validation at the LETF to verify it is functioning properly. The center’s Engineering Directorate and the Ground Systems Development and Operations Program are overseeing processing and testing of the umbilicals.

STS-40 crew trains in JSC's SLS mockup located in Bldg 36

NASA Image and Video Library

1987-03-10

STS-40 Payload Specialist Millie Hughes-Fulford along with backup payload specialist Robert Ward Phillips familiarize themselves with Spacelab Life Sciences 1 (SLS-1) equipment. The two scientists are in JSC's Life Sciences Project Division (LSPD) SLS mockup located in the Bioengineering and Test Support Facility Bldg 36. Hughes-Fulford, in the center aisle, pulls equipment from an overhead stowage locker while Phillips, in the foreground, experiments with the baroreflex neck pressure chamber at Rack 11. The baroreflex collar will be used in conjuction with Experiment No. 022, Influence of Weightlessness Upon Human Autonomic Cardiovascular Control. Behind Phillips in the center aisle are body mass measurement device (BMMD) (foreground) and the stowed bicycle ergometer.

SRB Processing Facilities Media Event

NASA Image and Video Library

2016-03-01

Inside the Booster Fabrication Facility (BFF) at NASA’s Kennedy Space Center in Florida, members of the news media view a forward skirt that will be used on a solid rocket booster for NASA’s Space Launch System (SLS) rocket. Orbital ATK is a contractor for NASA’s Marshall Space Flight Center in Alabama, and operates the BFF to prepare aft booster segments and hardware for the SLS solid rocket boosters. Rick Serfozo, Orbital ATK Florida site director, talks to the media. The SLS rocket and Orion spacecraft will launch on Exploration Mission-1 in 2018. The Ground Systems Development and Operations Program is preparing the infrastructure to process and launch spacecraft for deep-space missions and the journey to Mars.

Space Launch System Advanced Development Office, FY 2013 Annual Report

NASA Technical Reports Server (NTRS)

Crumbly, C. M.; Bickley, F. P.; Hueter, U.

2013-01-01

The Advanced Development Office (ADO), part of the Space Launch System (SLS) program, provides SLS with the advanced development needed to evolve the vehicle from an initial Block 1 payload capability of 70 metric tons (t) to an eventual capability Block 2 of 130 t, with intermediary evolution options possible. ADO takes existing technologies and matures them to the point that insertion into the mainline program minimizes risk. The ADO portfolio of tasks covers a broad range of technical developmental activities. The ADO portfolio supports the development of advanced boosters, upper stages, and other advanced development activities benefiting the SLS program. A total of 34 separate tasks were funded by ADO in FY 2013.

Interim Cryogenic Propulsion Stage (ICPS) Transport from DOC to

NASA Image and Video Library

2017-07-26

The Interim Cryogenic Propulsion Stage (ICPS) for NASA's Space Launch System (SLS) rocket, packed inside a canister, exits the United Launch Alliance (ULA) Delta Operations Center near Space Launch Complex 37 at Cape Canaveral Air Force Station for its move to the Space Station Processing Facility at NASA's Kennedy Space Center in Florida. The ICPS is the first integrated piece of flight hardware to arrive for the SLS. It is the in-space stage that is located toward the top of the rocket, between the Launch Vehicle Stage Adapter and the Orion Spacecraft Adapter. It will provide some of the in-space propulsion during Orion's first flight test atop the SLS on Exploration Mission-1.

Interim Cryogenic Propulsion Stage (ICPS) Prep for Transport fro

NASA Image and Video Library

2017-07-25

The Interim Cryogenic Propulsion Stage (ICPS) for NASA's Space Launch System (SLS) rocket is packed inside a canister and ready to be moved from the United Launch Alliance (ULA) Delta Operations Center near Space Launch Complex 37 at Cape Canaveral Air Force Station to the Space Station Processing Facility at NASA's Kennedy Space Center in Florida. The ICPS is the first integrated piece of flight hardware to arrive for the SLS. It is the in-space stage that is located toward the top of the rocket, between the Launch Vehicle Stage Adapter and the Orion Spacecraft Adapter. It will provide some of the in-space propulsion during Orion's first flight test atop the SLS on Exploration Mission-1.

Interim Cryogenic Propulsion Stage (ICPS) for EM-1 Transport fro

NASA Image and Video Library

2017-04-11

The Interim Cryogenic Propulsion Stage (ICPS) for NASA's Space Launch System (SLS) rocket has been moved on its transport stand by truck out of the United Launch Alliance (ULA) Horizontal Integration Facility near Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida. The ICPS will be transported to the Delta Operations Center. The ICPS is the first integrated piece of flight hardware to arrive for the SLS. It is the in-space stage that is located toward the top of the rocket, between the Launch Vehicle Stage Adapter and the Orion Spacecraft Adapter. It will provide some of the in-space propulsion during Orion's first flight test atop the SLS on Exploration Mission-1.

Interim Cryogenic Propulsion Stage (ICPS) for EM-1 Transport fro

NASA Image and Video Library

2017-04-11

The Interim Cryogenic Propulsion Stage (ICPS) for NASA's Space Launch System (SLS) rocket is moved on its transport stand by truck out of the United Launch Alliance (ULA) Horizontal Integration Facility near Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida. The ICPS will be transported to the Delta Operations Center. The ICPS is the first integrated piece of flight hardware to arrive for the SLS. It is the in-space stage that is located toward the top of the rocket, between the Launch Vehicle Stage Adapter and the Orion Spacecraft Adapter. It will provide some of the in-space propulsion during Orion's first flight test atop the SLS on Exploration Mission-1.

Interim Cryogenic Propulsion Stage (ICPS) for EM-1 Transport fro

NASA Image and Video Library

2017-04-11

The Interim Cryogenic Propulsion Stage (ICPS) for NASA's Space Launch System (SLS) rocket has been moved on its transport stand by truck out of the United Launch Alliance (ULA) Horizontal Integration Facility near Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida, on its way to the Delta Operations Center. The ICPS is the first integrated piece of flight hardware to arrive for the SLS. It is the in-space stage that is located toward the top of the rocket, between the Launch Vehicle Stage Adapter and the Orion Spacecraft Adapter. It will provide some of the in-space propulsion during Orion's first flight test atop the SLS on Exploration Mission-1.

Interim Cryogenic Propulsion Stage (ICPS) Transport from DOC to

NASA Image and Video Library

2017-07-26

The Interim Cryogenic Propulsion Stage (ICPS) for NASA's Space Launch System (SLS) rocket, packed inside a canister, is transported from the United Launch Alliance (ULA) Delta Operations Center near Space Launch Complex 37 at Cape Canaveral Air Force Station along the route to the Space Station Processing Facility at NASA's Kennedy Space Center in Florida. The ICPS is the first integrated piece of flight hardware to arrive for the SLS. It is the in-space stage that is located toward the top of the rocket, between the Launch Vehicle Stage Adapter and the Orion Spacecraft Adapter. It will provide some of the in-space propulsion during Orion's first flight test atop the SLS on Exploration Mission-1.

Interim Cryogenic Propulsion Stage (ICPS) for EM-1 Transport fro

NASA Image and Video Library

2017-04-11

The Interim Cryogenic Propulsion Stage (ICPS) for NASA's Space Launch System (SLS) rocket has been moved on its transport stand by truck out of the United Launch Alliance (ULA) Horizontal Integration Facility near Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida, and is on its way to the Delta Operations Center. The ICPS is the first integrated piece of flight hardware to arrive for the SLS. It is the in-space stage that is located toward the top of the rocket, between the Launch Vehicle Stage Adapter and the Orion Spacecraft Adapter. It will provide some of the in-space propulsion during Orion's first flight test atop the SLS on Exploration Mission 1.

SLS Scale Model Acoustic Test Liftoff Results and Comparisons

NASA Technical Reports Server (NTRS)

Houston, Janice; Counter, Douglas; Giacomoni, Clothilde

2015-01-01

The liftoff phase induces acoustic loading over a broad frequency range for a launch vehicle. These external acoustic environments are then used in the prediction of internal vibration responses of the vehicle and components which result in the qualification levels. Thus, predicting these liftoff acoustic (LOA) environments is critical to the design requirements of any launch vehicle. If there is a significant amount of uncertainty in the predictions or if acoustic mitigation options must be implemented, a subscale acoustic test is a feasible design phase test option to verify the LOA environments. The NASA Space Launch System (SLS) program initiated the Scale Model Acoustic Test (SMAT) to verify the predicted SLS LOA environments.

Platform C South Arrival

NASA Image and Video Library

2016-08-05

A heavy load transport truck from Tillett Heavy Hauling in Titusville, Florida, arrives at the Vehicle Assembly Building (VAB) at NASA’s Kennedy Space Center in Florida, carrying the second section of the first half of the C-level work platforms, C South, for the agency’s Space Launch System (SLS) rocket. The platform will be offloaded in the VAB staging area in the west parking lot. The Ground Systems Development and Operations Program is overseeing upgrades and modifications to VAB High Bay 3 to support processing of the SLS and Orion spacecraft. A total of 10 levels of new platforms, 20 platform halves altogether, will surround the SLS rocket and Orion spacecraft and provide access for testing and processing.

Platform C South Arrival

NASA Image and Video Library

2016-08-04

A heavy load transport truck from Tillett Heavy Hauling in Titusville, Florida, arrives at the Vehicle Assembly Building (VAB) at NASA’s Kennedy Space Center in Florida, carrying a section of the first half of the C-level work platforms, C south, for the agency’s Space Launch System (SLS) rocket. The platform will be delivered to the VAB staging area in the west parking lot. The Ground Systems Development and Operations Program is overseeing upgrades and modifications to VAB High Bay 3 to support processing of the SLS and Orion spacecraft. A total of 10 levels of new platforms, 20 platform halves altogether, will surround the SLS rocket and Orion spacecraft and provide access for testing and processing.

Orion and SLS showcased at Michoud on This Week @NASA – January 29, 2016

NASA Image and Video Library

2016-01-29

A Jan. 26 event at NASA’s Michoud Assembly Facility in New Orleans, marked recently completed work by technicians there to weld together the pressure vessel for the next Orion deep space crew module. The event also was an opportunity for NASA officials to thank employees and to show the progress on Orion and the core stage of the agency’s Space Launch System (SLS) rocket. The Orion pressure vessel will be shipped to Kennedy Space Center in Florida next month, where engineers will continue to prepare it for the first flight of the SLS rocket. Also, Space station One-year crew update, New color movie of Ceres and NASA Day of Remembrance!

Quantification of Sesquiterpene Lactones in Asteraceae Plant Extracts: Evaluation of their Allergenic Potential

PubMed Central

Salapovic, Helena; Geier, Johannes; Reznicek, Gottfried

2013-01-01

Sesquiterpene lactones (SLs), mainly those with an activated exocyclic methylene group, are important allergens in Asteraceae (Compositae) plants. As a screening tool, the Compositae mix, consisting of five Asteraceae plant extracts with allergenic potential (feverfew, tansy, arnica, yarrow, and German chamomile) is part of several national patch test baseline series. However, the SL content of the Compositae mix may vary due to the source material. Therefore, a simple spectrophotometric method for the quantitative measurement of SLs with the α-methylene-γ-butyrolactone moiety was developed, giving the percentage of allergenic compounds in plant extracts. The method has been validated and five Asteraceae extracts, namely feverfew (Tanacetum parthenium L.), tansy (Tanacetum vulgare L.), arnica (Arnica montana L.), yarrow (Achillea millefolium L.), and German chamomile (Chamomilla recutita L. Rauschert) that have been used in routine patch test screening were evaluated. A good correlation could be found between the results obtained using the proposed spectrophotometric method and the corresponding clinical results. Thus, the introduced method is a valuable tool for evaluating the allergenic potential and for the simple and efficient quality control of plant extracts with allergenic potential. PMID:24106675

Blood collection kit for Space Lab 1

NASA Image and Video Library

1981-02-02

S81-26158 (Feb 1981) --- A close-up view of a training version of a STS-40/SLS-1 blood kit. Blood samples from crewmembers are critical to a number of Space Life Sciences-1 (SLS-1) investigations. One day's collection equipment, color coded for each crewmember, is neatly organized in the kit.

STS-40 Payload Specialist Hughes-Fulford "flies" through SLS-1 module

NASA Image and Video Library

1991-06-14

STS040-212-006 (5-14 June 1991) --- Payload specialist Millie Hughes-Fulford floats through the Spacelab Life Sciences (SLS-1) module aboard the Earth-orbiting Columbia. Astronaut James P. Bagian, mission specialist, is at the blood draw station in the background. The scene was photographed with a 35mm camera.

Antimicrobial activity and inactivation mechanism of lactonic and free acid sophorolipids against Escherichia coli O157:H7

USDA-ARS?s Scientific Manuscript database

In this study, we synthesized sophorolipids (SLs) from glucose and either palmitic, stearic or oleic acid via fermentation using the osmophilic yeast Starmerella bombicola, purified and separated the SLs into lactonic and free-acid forms and assessed their antimicrobial efficacy against 5 strains of...

Research in Second Language Studies at Michigan State University

ERIC Educational Resources Information Center

White, Benjamin; , Fei, Fei; Russell, Marthe

2009-01-01

The Second Language Studies (SLS) Program was established in 2005 with the express purpose of providing "a firm foundation in the field of Second Language Acquisition and its application to current second language research and teaching" (http://sls.msu.edu). Under the leadership of Professor Susan Gass, the program has grown to include…

The Problems of Multiple Feedback Estimation.

ERIC Educational Resources Information Center

Bulcock, Jeffrey W.

The use of two-stage least squares (2SLS) for the estimation of feedback linkages is inappropriate for nonorthogonal data sets because 2SLS is extremely sensitive to multicollinearity. It is argued that what is needed is use of a different estimating criterion than the least squares criterion. Theoretically the variance normalization criterion has…

Normalization Ridge Regression in Practice II: The Estimation of Multiple Feedback Linkages.

ERIC Educational Resources Information Center

Bulcock, J. W.

The use of the two-stage least squares (2 SLS) procedure for estimating nonrecursive social science models is often impractical when multiple feedback linkages are required. This is because 2 SLS is extremely sensitive to multicollinearity. The standard statistical solution to the multicollinearity problem is a biased, variance reduced procedure…

Risk Assessment and scaling for the SLS LOx ET

NASA Technical Reports Server (NTRS)

Osipov, Viatcheslav V.; Hafiychuk, Halyna; Devine, Ekaterina V.; Khasin, Michael; Smelyanskiy, Vadim N.

2012-01-01

In this report we analyze the transpiration cooling by He bubble injection of the long LOx tank feedline heated by the environment heat. We consider possible hazards that can arise in the proposed design of the SLS core stage where the feedline length is much longer than that used in the Space Shuttle.

Histological changes to the skin of Merino sheep following deep dermal and subcutaneous injections of sodium lauryl sulfate.

PubMed

Lee, E J; Rothwell, J T

2010-04-01

To characterise the changes caused to sheep skin by deep dermal and subcutaneous injections of sodium lauryl sulfate (SLS) and describe the subsequent healing process. On 6 sheep 20 small areas of skin were each given deep dermal and subcutaneous injections of 0.2 mL of 7% SLS. Biopsies were collected at intervals up to 28 days after treatment and the histological changes in each of the treated skin samples were assessed and graded. There was no evidence of alterations in behaviour, weight gain or appetite of the sheep following the injections. Initial swelling of the treated site subsided by day 14, leaving a firm, slightly raised crust. At day 21, the treated area was depressed and covered by a scab, which sloughed completely by day 28. There was necrosis of the subcutis and deep dermis 2 min after treatment, followed by inflammation, fibroplasia, angiogenesis and tissue remodelling. Injection of SLS caused almost immediate local necrosis followed by eschar formation, sloughing and scarring of treated skin. Deep dermal and subcutaneous SLS is potentially useful as a chemical alternative to mulesing.

Effect of Powder Size and Shape on the SLS Processability and Mechanical Properties of a TPU Elastomer

NASA Astrophysics Data System (ADS)

Dadbakhsh, Sasan; Verbelen, Leander; Vandeputte, Tom; Strobbe, Dieter; Van Puyvelde, Peter; Kruth, Jean-Pierre

This work investigates the influence of powder size/shape on selective laser sintering (SLS) of a thermoplastic polyurethane (TPU) elastomer. It examines a TPU powder which had been cryogenically milled in two different sizes; coarse powder (D50∼200μm) with rough surfaces in comparison with a fine powder (D50∼63μm) with extremely fine flow additives. It is found that the coarse powder coalesces at lower temperatures and excessively smokes during the SLS processing. In comparison, the fine powder with flow additives is better processable at significantly higher powder bed temperatures, allowing a lower optimum laser energy input which minimizes smoking and degradation of the polymer. In terms of mechanical properties, good coalescence of both powders lead to parts with acceptable shear-punch strengths compared to injection molded parts. However, porosity and degradation from the optimum SLS parameters of the coarse powder drastically reduce the tensile properties to about one-third of the parts made from the fine powders as well as those made by injection molding (IM).

Selective Laser Sintering of Porous Silica Enabled by Carbon Additive

PubMed Central

Chang, Shuai; Li, Liqun; Lu, Li

2017-01-01

The aim of this study is to investigate the possibility of a freeform fabrication of porous ceramic parts through selective laser sintering (SLS). SLS was proposed to manufacture ceramic green parts because this additive manufacturing technique can be used to fabricate three-dimensional objects directly without a mold, and the technique has the capability of generating porous ceramics with controlled porosity. However, ceramic printing has not yet fully achieved its 3D fabrication capabilities without using polymer binder. Except for the limitations of high melting point, brittleness, and low thermal shock resistance from ceramic material properties, the key obstacle lies in the very poor absorptivity of oxide ceramics to fiber laser, which is widely installed in commercial SLS equipment. An alternative solution to overcome the poor laser absorptivity via improving material compositions is presented in this study. The positive effect of carbon additive on the absorptivity of silica powder to fiber laser is discussed. To investigate the capabilities of the SLS process, 3D porous silica structures were successfully prepared and characterized. PMID:29144425

Strigolactone biology: genes, functional genomics, epigenetics and applications.

PubMed

Makhzoum, Abdullah; Yousefzadi, Morteza; Malik, Sonia; Gantet, Pascal; Tremouillaux-Guiller, Jocelyne

2017-03-01

Strigolactones (SLs) represent an important new plant hormone class marked by their multifunctional role in plant and rhizosphere interactions. These compounds stimulate hyphal branching in arbuscular mycorrhizal fungi (AMF) and seed germination of root parasitic plants. In addition, they are involved in the control of plant architecture by inhibiting bud outgrowth as well as many other morphological and developmental processes together with other plant hormones such as auxins and cytokinins. The biosynthetic pathway of SLs that are derived from carotenoids was partially decrypted based on the identification of mutants from a variety of plant species. Only a few SL biosynthetic and regulated genes and related regulatory transcription factors have been identified. However, functional genomics and epigenetic studies started to give first elements on the modality of the regulation of SLs related genes. Since they control plant architecture and plant-rhizosphere interaction, SLs start to be used for agronomical and biotechnological applications. Furthermore, the genes involved in the SL biosynthetic pathway and genes regulated by SL constitute interesting targets for plant breeding. Therefore, it is necessary to decipher and better understand the genetic determinants of their regulation at different levels.

Spacelab

NASA Image and Video Library

1991-06-01

The laboratory module in the cargo bay of the Space Shuttle Orbiter Columbia was photographed during the Spacelab Life Science-1 (SLS-1) mission. SLS-1 was the first Spacelab mission dedicated solely to life sciences. The main purpose of the SLS-1 mission was to study the mechanisms, magnitudes, and time courses of certain physiological changes that occur during space flight, to investigate the consequences of the body's adaptation to microgravity and readjustment to Earth's gravity, and to bring the benefits back home to Earth. The mission was designed to explore the responses of the heart, lungs, blood vessels, kidneys, and hormone-secreting glands to microgravity and related body fluid shifts; examine the causes of space motion sickness; and study changes in the muscles, bones and cells. The five body systems being studied were: The Cardiovascular/Cardiopulmonary System (heart, lungs, and blood vessels), the Renal/Endocrine System (kidney and hormone-secreting organs), the Immune System (white blood cells), the Musculoskeletal System (muscles and bones), and the Neurovestibular System (brain and nerves, eyes, and irner ear). The SLS-1 was launched aboard the Space Shuttle Orbiter Columbia (STS-40) on June 5, 1995.

Developmentally Regulated Sphingolipid Synthesis in African Trypanosomes

PubMed Central

Sutterwala, Shaheen S.; Hsu, Fong Fu; Sevova, Elitza S.; Schwartz, Kevin J.; Zhang, Kai; Key, Phillip; Turk, John; Beverley, Stephen M.; Bangs, James D.

2008-01-01

Sphingolipids are essential components of eukaryotic membranes, and many unicellular eukaryotes, including kinetoplastid protozoa, are thought to synthesize exclusively inositol phosphorylceramide (IPC). Here we characterize sphingolipids from Trypanosoma brucei, and a trypanosome sphingolipid synthase gene family (TbSLS1-4) that is orthologous to Leishmania IPC synthase. Procyclic trypanosomes contain IPC, but also sphingomyelin, while surprisingly bloodstream stage parasites contain sphingomyelin and ethanolamine phosphorylceramide (EPC), but no detectable IPC. In vivo fluorescent ceramide labeling confirmed stage specific biosynthesis of both sphingomyelin and IPC. Expression of TbSLS4 in Leishmania resulted in production of sphingomyelin and EPC suggesting that the TbSLS gene family has bi-functional synthase activity. RNAi silencing of TbSLS1-4 in bloodstream trypanosomes led to rapid growth arrest and eventual cell death. Ceramide levels were increased >3-fold by silencing suggesting a toxic downstream effect mediated by this potent intracellular messenger. Topology predictions support a revised six transmembrane domain model for the kinetoplastid sphingolipid synthases consistent with the proposed mammalian SM synthase structure. This work reveals novel diversity and regulation in sphingolipid metabolism in this important group of human parasites. PMID:18699867

Potential applications of the white rot fungus Pleurotus in bioregenerative life support systems

NASA Astrophysics Data System (ADS)

Manukovsky, N. S.; Kovalev, V. S.; Yu, Ch.; Gurevich, Yu. L.; Liu, H.

Earlier we demonstrated the possibility of using soil-like substrate SLS for plant cultivation in bioregenerative life support systems BLSS We suggest dividing the process of SLS bioregeneration at BLSS conditions into two stages At the first stage plant residues should be used for growing of white rot fungus Pleurotus ostreatus Pleurotus florida etc The fruit bodies could be used as food Spent mushroom compost is carried in SLS and treated by microorganisms and worms at the second stage The possibility of extension of human food ration is only one of the reasons for realization of the suggested two-stage SLS regeneration scheme people s daily consumption of mushrooms is limited to 200 -250 g of wet weight or 20 -25 g of dry weight Multiple tests showed what is more important is that inclusion of mushrooms into the system cycle scheme contributes through various mechanisms to the more stable functioning of vegetative cenosis in general Taking into account the given experimental data we determined the scheme of mushroom module material balance The technological peculiarities of mushroom cultivation at BLSS conditions are being discussed

KSC-04PD-0008

NASA Technical Reports Server (NTRS)

2004-01-01

KENNEDY SPACE CENTER, FLA. -- In the Space Life Sciences (SLS) Lab, Jan Bauer, with Dynamac Corp., weighs samples of onion tissue for processing in the elemental analyzer behind it. The equipment analyzes for carbon, hydrogen, nitrogen and sulfur. The 100,000 square-foot SLS houses labs for NASAs ongoing research efforts, microbiology/microbial ecology studies and analytical chemistry labs. Also calling the new lab home are facilities for space flight-experiment and flight-hardware development, new plant growth chambers, and an Orbiter Environment Simulator that will be used to conduct ground control experiments in simulated flight conditions for space flight experiments. The SLS Lab, formerly known as the Space Experiment Research and Processing Laboratory or SERPL, provides space for NASAs Life Sciences Services contractor Dynamac Corporation, Bionetics Corporation, and researchers from the University of Florida. NASAs Office of Biological and Physical Research will use the facility for processing life sciences experiments that will be conducted on the International Space Station. The SLS Lab is the magnet facility for the International Space Research Park at KSC being developed in partnership with Florida Space Authority.

How the 2SLS/IV estimator can handle equality constraints in structural equation models: a system-of-equations approach.

PubMed

Nestler, Steffen

2014-05-01

Parameters in structural equation models are typically estimated using the maximum likelihood (ML) approach. Bollen (1996) proposed an alternative non-iterative, equation-by-equation estimator that uses instrumental variables. Although this two-stage least squares/instrumental variables (2SLS/IV) estimator has good statistical properties, one problem with its application is that parameter equality constraints cannot be imposed. This paper presents a mathematical solution to this problem that is based on an extension of the 2SLS/IV approach to a system of equations. We present an example in which our approach was used to examine strong longitudinal measurement invariance. We also investigated the new approach in a simulation study that compared it with ML in the examination of the equality of two latent regression coefficients and strong measurement invariance. Overall, the results show that the suggested approach is a useful extension of the original 2SLS/IV estimator and allows for the effective handling of equality constraints in structural equation models. © 2013 The British Psychological Society.

Space Launch System Complex Decision-Making Process

NASA Technical Reports Server (NTRS)

Lyles, Garry; Flores, Tim; Hundley, Jason; Monk, Timothy; Feldman,Stuart

2012-01-01

The Space Shuttle program has ended and elements of the Constellation Program have either been cancelled or transitioned to new NASA exploration endeavors. The National Aeronautics and Space Administration (NASA) has worked diligently to select an optimum configuration for the Space Launch System (SLS), a heavy lift vehicle that will provide the foundation for future beyond low earth orbit (LEO) large-scale missions for the next several decades. From Fall 2010 until Spring 2011, an SLS decision-making framework was formulated, tested, fully documented, and applied to multiple SLS vehicle concepts at NASA from previous exploration architecture studies. This was a multistep process that involved performing figure of merit (FOM)-based assessments, creating Pass/Fail gates based on draft threshold requirements, performing a margin-based assessment with supporting statistical analyses, and performing sensitivity analysis on each. This paper focuses on the various steps and methods of this process (rather than specific data) that allowed for competing concepts to be compared across a variety of launch vehicle metrics in support of the successful completion of the SLS Mission Concept Review (MCR) milestone.

Redirection of sphingolipid metabolism toward de novo synthesis of ethanolamine in Leishmania

PubMed Central

Zhang, Kai; Pompey, Justine M; Hsu, Fong-Fu; Key, Phillip; Bandhuvula, Padmavathi; Saba, Julie D; Turk, John; Beverley, Stephen M

2007-01-01

In most eukaryotes, sphingolipids (SLs) are critical membrane components and signaling molecules. However, mutants of the trypanosomatid protozoan Leishmania lacking serine palmitoyltransferase (spt2−) and SLs grow well, although they are defective in stationary phase differentiation and virulence. Similar phenotypes were observed in sphingolipid (SL) mutant lacking the degradatory enzyme sphingosine 1-phosphate lyase (spl−). This epistatic interaction suggested that a metabolite downstream of SLs was responsible. Here we show that unlike other organisms, the Leishmania SL pathway has evolved to be the major route for ethanolamine (EtN) synthesis, as EtN supplementation completely reversed the viability and differentiation defects of both mutants. Thus Leishmania has undergone two major metabolic shifts: first in de-emphasizing the metabolic roles of SLs themselves in growth, signaling, and maintenance of membrane microdomains, which may arise from the unique combination of abundant parasite lipids; Second, freed of typical SL functional constraints and a lack of alternative routes to produce EtN, Leishmania redirected SL metabolism toward bulk EtN synthesis. Our results thus reveal a striking example of remodeling of the SL metabolic pathway in Leishmania. PMID:17290222

NASA's Space Launch System: A Flagship for Exploration Beyond Earth's Orbit

NASA Technical Reports Server (NTRS)

May, Todd A.; Creech, Stephen D.

2012-01-01

The National Aeronautics and Space Administration s (NASA s) Space Launch System (SLS) Program, managed at the Marshall Space Flight Center, is making measurable progress toward delivering a new capability for human and scientific exploration. To arrive at the current plan, government and industry experts carefully analyzed hundreds of architecture options and selected the one clear solution to stringent requirements for safety, affordability, and sustainability over the decades that the rocket will be in operation. Slated for its maiden voyage in 2017, the SLS will provide a platform for further cooperation in space based on the International Space Station model. This briefing will focus on specific progress that has been made by the SLS team in its first year, as well as provide a framework for evolving the vehicle for far-reaching missions to destinations such as near-Earth asteroids, Lagrange Points, and Mars. As this briefing will show, the SLS will serve as an infrastructure asset for robotic and human scouts of all nations by harnessing business and technological innovations to deliver sustainable solutions for space exploration.

NASA's Space Launch System: Deep-Space Delivery for SmallSats

NASA Technical Reports Server (NTRS)

Robinson, Kimberly F.; Norris, George

2017-01-01

Designed for human exploration missions into deep space, NASA's Space Launch System (SLS) represents a new spaceflight infrastructure asset, enabling a wide variety of unique utilization opportunities. While primarily focused on launching the large systems needed for crewed spaceflight beyond Earth orbit, SLS also offers a game-changing capability for the deployment of small satellites to deep-space destinations, beginning with its first flight. Currently, SLS is making rapid progress toward readiness for its first launch in two years, using the initial configuration of the vehicle, which is capable of delivering more than 70 metric tons (t) to Low Earth Orbit (LEO). Planning is underway for smallsat accomodations on future configurations of the vehicle, which will present additional opportunities. This paper will include an overview of the SLS vehicle and its capabilities, including the current status of progress toward first launch. It will also explain the current and future opportunities the vehicle offers for small satellites, including an overview of the CubeSat manifest for Exploration Mission-1 in 2018 and a discussion of future capabilities.

SSME to RS-25: Challenges of Adapting a Heritage Engine to a New Vehicle Architecture

NASA Technical Reports Server (NTRS)

Ballard, Richard O.

2015-01-01

Following the cancellation of the Constellation program and retirement of the Space Shuttle, NASA initiated the Space Launch System (SLS) program to provide next-generation heavy lift cargo and crew access to space. A key constituent of the SLS architecture is the RS-25 engine, also known as the Space Shuttle Main Engine (SSME). The RS-25 was selected to serve as the main propulsion system for the SLS core stage in conjunction with the solid rocket boosters. This selection was largely based on the maturity and extensive experience gained through 135 missions, 3000+ ground tests, and over a million seconds total accumulated hot-fire time. In addition, there were also over a dozen functional flight assets remaining from the Space Shuttle program that could be leveraged to support the first four flights. However, while the RS-25 is a highly mature system, simply unbolting it from the Space Shuttle boat-tail and installing it on the new SLS vehicle is not a "plug-and-play" operation. In addition to numerous technical integration details involving changes to significant areas such as the environments, interface conditions, technical performance requirements, operational constraints and so on, there were other challenges to be overcome in the area of replacing the obsolete engine control system (ECS). While the magnitude of accomplishing this effort was less than that needed to develop and field a new clean-sheet engine system, the path to the first flight of SLS has not been without unexpected challenges.

Game Changing: NASA's Space Launch System and Science Mission Design

NASA Technical Reports Server (NTRS)

Creech, Stephen D.

2013-01-01

NASA s Marshall Space Flight Center (MSFC) is directing efforts to build the Space Launch System (SLS), a heavy-lift rocket that will carry the Orion Multi-Purpose Crew Vehicle (MPCV) and other important payloads far beyond Earth orbit (BEO). Its evolvable architecture will allow NASA to begin with Moon fly-bys and then go on to transport humans or robots to distant places such as asteroids and Mars. Designed to simplify spacecraft complexity, the SLS rocket will provide improved mass margins and radiation mitigation, and reduced mission durations. These capabilities offer attractive advantages for ambitious missions such as a Mars sample return, by reducing infrastructure requirements, cost, and schedule. For example, if an evolved expendable launch vehicle (EELV) were used for a proposed mission to investigate the Saturn system, a complicated trajectory would be required - with several gravity-assist planetary fly-bys - to achieve the necessary outbound velocity. The SLS rocket, using significantly higher C3 energies, can more quickly and effectively take the mission directly to its destination, reducing trip time and cost. As this paper will report, the SLS rocket will launch payloads of unprecedented mass and volume, such as "monolithic" telescopes and in-space infrastructure. Thanks to its ability to co-manifest large payloads, it also can accomplish complex missions in fewer launches. Future analyses will include reviews of alternate mission concepts and detailed evaluations of SLS figures of merit, helping the new rocket revolutionize science mission planning and design for years to come.

Engineering of hydrogenated two-dimensional h-BN/C superlattices as electrostatic substrates.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, Zhun; Zhong, Xiaoliang; Yan, Hui

2016-01-14

Hybridized two-dimensional materials incorporating domains from the hexagonal boron nitride (h-BN) and graphene is an interesting branch of materials science due to their highly tunable electronic properties. In the present study, we investigate the hydrogenated two-dimensional (2D) h-BN/C superlattices (SLs) with zigzag edges using first-principles calculations. We found that the domain width, the phase ratio, and the vertical dipole orientation all have significant influence on the stability of SLs. The electronic reconstruction is associated with the lateral polar discontinuities at the zigzag edges and the vertically polarized (B2N2H4)(m) domains, which modifies the electronic structures and the spatial potential of themore » SLs significantly. Furthermore, we demonstrate that the hydrogenated 2D h-BN/C SLs can be applied in engineering the electronic structure of graphene: laterally-varying doping can be achieved by taking advantage of the spatial variation of the surface potential of the SLs. By applying an external vertical electric field on these novel bidirectional heterostructures, graphene doping levels and band offsets can be tuned to a wide range, such that the graphene doping profile can be switched from the bipolar (p-n junction) to unipolar (n(+)-n junction) mode. It is expected that such bidirectional heterostructures provide an effective approach for developing novel nanoscale electronic devices and improving our understanding of the fundamentals of low-dimensional materials.« less

Hidden Figures To Modern Figures- Students See SLS Rocket at Michoud

NASA Image and Video Library

2017-01-09

New Orleans teacher Katherine Michelle Sanders of St. Peter Claver School, takes her 7th grade science on a tour of nearby NASA’s Michoud Assembly Facility to see where the Space Launch System - the world’s most powerful rocket - is being built. Sanders is the granddaughter of famed NASA scientist Katherine Johnson who was featured in the book and movie, Hidden Figures. Sanders discusses how her grandmother’s work inspired her and why she wanted her students to learn about NASA’s plan to explore deep space. Sanders followed her grandmother's footsteps, as Katherine Johnson was also a teacher before going to work for the National Advisory Committee for Aeronautics (NACA) and later at NASA's Langley Research Center as a human computer. Due to Johnson’s historical role as one of the first African-American women to work as a NASA scientist, she was awarded the Presidential Medal of Freedom by President Barack Obama in 2015. In this video, Michoud Director Bobby Watkins and NASA engineer Renee Horton speak with the students about key components building the SLS rocket, including the Vertical Assembly Center - a large robotic tool for manufacturing hardware - and a liquid hydrogen tank that will hold fuel for the first mission, and a liquid hydrogen tank that will hold fuel for the first SLS mission. For more information on SLS, visit www.nasa.gov/sls. For more information on Michoud Assembly Facility, visit www.nasa.gov/centers/marshall/michoud/index.html

Effects of aqueous extract of soil-like substrate made from three different materials on seed germination and seedling growth of rice

NASA Astrophysics Data System (ADS)

Shao, Lingzhi; Fu, Yuming; Fu, Wenting; Yan, Min; Li, Leyuan; Liu, Hong

2014-03-01

Biologically processing rice and wheat straws into soil-like substrate (SLS) and then reusing them in plant cultivation system to achieve waste recycle is very crucially important in Bioregenerative life support system (BLSS). However, rice is a plant with strong allelopathic potential. It is not clear yet that what kinds of raw materials can be processed into proper SLS to grow rice in BLSS. Therefore, in this study, the aqueous extract of SLS made from three different materials including rice straw, wheat straw and rice-wheat straw mixture was utilized to investigate its effects on the seed germination and seedling growth of rice. The gradients of the extract concentrations (soil:water) were 1:3, 1:5, 1:9, and 1:15 with deionized water used as control. The effects of different types of SLS on seed germination and seedling vitality of rice were confirmed by analyzing the germination rate, seedling length, root length, the fresh weight and other indicants. In addition, based on the analysis towards pH, organic matter composition and other factors of the SLS as well as the chlorophyll, hormone content of rice, and the mechanism of the inhibition was speculated in order to explore the preventive methods of the phenomenon. Finally, the feasibility of cultivating rice on SLSs made from the raw materials mentioned above was evaluated and wheat raw was determined as the most appropriate material for growing rice.

Game changing: NASA's space launch system and science mission design

NASA Astrophysics Data System (ADS)

Creech, S. D.

NASA's Marshall Space Flight Center (MSFC) is directing efforts to build the Space Launch System (SLS), a heavy-lift rocket that will carry the Orion Multi-Purpose Crew Vehicle (MPCV) and other important payloads far beyond Earth orbit (BEO). Its evolvable architecture will allow NASA to begin with Moon fly-bys and then go on to transport humans or robots to distant places such as asteroids and Mars. Designed to simplify spacecraft complexity, the SLS rocket will provide improved mass margins and radiation mitigation, and reduced mission durations. These capabilities offer attractive advantages for ambitious missions such as a Mars sample return, by reducing infrastructure requirements, cost, and schedule. For example, if an evolved expendable launch vehicle (EELV) were used for a proposed mission to investigate the Saturn system, a complicated trajectory would be required - with several gravity-assist planetary fly-bys - to achieve the necessary outbound velocity. The SLS rocket, using significantly higher characteristic energy (C3) energies, can more quickly and effectively take the mission directly to its destination, reducing trip time and cost. As this paper will report, the SLS rocket will launch payloads of unprecedented mass and volume, such as “ monolithic” telescopes and in-space infrastructure. Thanks to its ability to co-manifest large payloads, it also can accomplish complex missions in fewer launches. Future analyses will include reviews of alternate mission concepts and detailed evaluations of SLS figures of merit, helping the new rocket revolutionize science mission planning and design for years to come.

Vibrational Sum Frequency Generation Spectroscopy Study of Hydrous Species in Soda Lime Silica Float Glass.

PubMed

Luo, Jiawei; Banerjee, Joy; Pantano, Carlo G; Kim, Seong H

2016-06-21

It is generally accepted that the mechanical properties of soda lime silica (SLS) glass can be affected by the interaction between sodium ions and hydrous species (silanol groups and water molecules) in its surface region. While the amount of these hydrous species can be estimated from hydrogen profiles and infrared spectroscopy, their chemical environment in the glass network is still not well understood. This work employed vibrational sum frequency generation (SFG) spectroscopy to investigate the chemical environment of hydrous species in the surface region of SLS float glass. SLS float glass shows sharp peaks in the OH stretching vibration region in SFG spectra, while the OH stretch peaks of glasses that do not have leachable sodium ions and the OH peaks of water molecules in condensed phases are normally broad due to fast hydrogen bonding dynamics. The hydrous species responsible for the sharp SFG peaks for the SLS float glass were found to be thermodynamically more stable than physisorbed water molecules, did not exchange with D2O, and were associated with the sodium concentration gradient in the dealkalized subsurface region. These results suggested that the hydrous species reside in static solvation shells defined by the silicate network with relatively slow hydrogen bonding dynamics, compared to physisorbed water layers on top of the glass surface. A putative radial distribution of the hydrous species within the SLS glass network was estimated based on the OH SFG spectral features, which could be compared with theoretical distributions calculated from computational simulations.

Shrinking lung syndrome as a manifestation of pleuritis: a new model based on pulmonary physiological studies.

PubMed

Henderson, Lauren A; Loring, Stephen H; Gill, Ritu R; Liao, Katherine P; Ishizawar, Rumey; Kim, Susan; Perlmutter-Goldenson, Robin; Rothman, Deborah; Son, Mary Beth F; Stoll, Matthew L; Zemel, Lawrence S; Sandborg, Christy; Dellaripa, Paul F; Nigrovic, Peter A

2013-03-01

The pathophysiology of shrinking lung syndrome (SLS) is poorly understood. We sought to define the structural basis for this condition through the study of pulmonary mechanics in affected patients. Since 2007, most patients evaluated for SLS at our institutions have undergone standardized respiratory testing including esophageal manometry. We analyzed these studies to define the physiological abnormalities driving respiratory restriction. Chest computed tomography data were post-processed to quantify lung volume and parenchymal density. Six cases met criteria for SLS. All presented with dyspnea as well as pleurisy and/or transient pleural effusions. Chest imaging results were free of parenchymal disease and corrected diffusing capacities were normal. Total lung capacities were 39%-50% of predicted. Maximal inspiratory pressures were impaired at high lung volumes, but not low lung volumes, in 5 patients. Lung compliance was strikingly reduced in all patients, accompanied by increased parenchymal density. Patients with SLS exhibited symptomatic and/or radiographic pleuritis associated with 2 characteristic physiological abnormalities: (1) impaired respiratory force at high but not low lung volumes; and (2) markedly decreased pulmonary compliance in the absence of identifiable interstitial lung disease. These findings suggest a model in which pleural inflammation chronically impairs deep inspiration, for example through neural reflexes, leading to parenchymal reorganization that impairs lung compliance, a known complication of persistently low lung volumes. Together these processes could account for the association of SLS with pleuritis as well as the gradual symptomatic and functional progression that is a hallmark of this syndrome.

Impacts of strigolactone on shoot branching under phosphate starvation in chrysanthemum (Dendranthema grandiflorum cv. Jinba)

PubMed Central

Xi, Lin; Wen, Chao; Fang, Shuang; Chen, Xiaoli; Nie, Jing; Chu, JinFang; Yuan, Cunquan; Yan, Cunyu; Ma, Nan; Zhao, Liangjun

2015-01-01

Chrysanthemum (Dendranthema grandiflorum cv. Jinba) shoot branching is determined by bud outgrowth during the vegetative growth stage. The degree of axillary bud outgrowth is highly influenced by environmental conditions, such as nutrient availability. Here, we demonstrated that phosphorus (Pi) starvation significantly reduces axillary bud outgrowth in chrysanthemum. A strigolactone (SL) biosynthesis gene, DgCCD7, was isolated and characterized as an ortholog of MAX3/DAD3/RMS5/D17. By using ultra-performance liquid chromatography coupled with mass spectrometry (UPLC-MS), three putative SLs were identified and levels of all three SLs showed strong increase under Pi starvation conditions. Determinations of the distribution of SLs and regulation of DgCCD7/8 in response to Pi changes in root indicate that SL acts systemically. However, temporal expression patterns of biosynthesis and signaling genes in nodes revealed that Pi starvation causes a local response of SL pathway. Treatment of node segments with or without auxin and Pi revealed that in the absence of exogenous auxin, Pi delayed axillary buds outgrowth and up-regulated local SL pathway genes. These data indicated that an auxin-SL regulatory loop responded to Pi starvation for delaying bud outgrowth locally, root biosynthesized SLs were transported acropetally and functioned in shoot branching inhibition under Pi starvation. We proposed that SLs contributed to chrysanthemum shoot branching control in response to Pi-limiting conditions in a systemic way. PMID:26442011

Chlorhexidine mouthwash and sodium lauryl sulphate dentifrice: do they mix effectively or interfere?

PubMed

Elkerbout, T A; Slot, D E; Bakker, E W P; Van der Weijden, G A

2016-02-01

What is the effectiveness of a chlorhexidine (CHX) mouthwash used in combination with a sodium lauryl sulphate (SLS) dentifrice on the parameters of plaque and gingivitis? MEDLINE-PubMed, Cochrane-CENTRAL, EMBASE and other electronic databases were searched up to July 2014. The inclusion criteria were (randomized) controlled clinical trials, subjects ≥18 years of age with good general health. Papers evaluating the effect of CHX mouthwash used in combination with SLS dentifrice or a dentifrice slurry compared with CHX mouthwash as a single oral hygiene intervention or in combination with an SLS-free dentifrice were included. From the eligible studies, data were extracted, and a meta-analysis was performed when feasible. Independent screening of 83 unique papers resulted in four eligible publications, with nine comparisons. The meta-analysis showed that when an SLS dentifrice was used as a slurry rinse, the interference on the plaque-inhibiting effect of a CHX mouthwash was significantly decreased (MD 0.33; P ≤ 0.00001; 95% CI: <0.24; 0.42>). No significant difference was observed when SLS dentifrice was applied as a paste in combination with CHX mouthwash (MD 0.08; P = 0.42; 95% CI: <-0.26; 0.11>). Descriptive and subgroup analyses support these findings. Moreover, the observed effect for the dentifrice paste occurred regardless of the order of use. This review demonstrates that when CHX mouthwash is recommended, it can be used in combination with an SLS dentifrice without any interference regarding its inhibiting effect on dental plaque, regardless of the order of use. Consequently, the collective evidence indicates that the combined use of dentifrice and CHX mouthwash is not contraindicated. However, this recommendation has been graded as moderate taking into account a potential publication bias because three of the four included studies emerged from the same research group. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Shrinking lung syndrome in systemic lupus erythematosus

PubMed Central

Borrell, Helena; Narváez, Javier; Alegre, Juan José; Castellví, Ivan; Mitjavila, Francesca; Aparicio, María; Armengol, Eulàlia; Molina-Molina, María; Nolla, Joan M.

2016-01-01

Abstract Shrinking lung syndrome (SLS) is a rare and less known complication mainly associated with systemic lupus erythematosus (SLE). In this study, we analyze the clinical features, investigation findings, approaches to management, and outcome in a case series of 9 adult patients with SLE and SLS diagnosed during a 35-year period in 3 referral tertiary care hospitals in Spain. Additionally, we reviewed 80 additional cases previously reported (PubMed 1965–2015). These 80 cases, together with our 9 patients, form the basis of the present analysis. The overall SLS prevalence in our SLE population was 1.1% (9/829). SLS may complicate SLE at any time over its course, and it usually occurs in patients without previous or concomitant major organ involvement. More than half of the patients had inactive lupus according to SELENA-systemic lupus erythematosus disease activity index (SLEDAI) scores. Typically, it presents with progressive exertional dyspnea of variable severity, accompanied by pleuritic chest pain in 76% of the cases. An important diagnostic delay is common. The diagnostic tools that showed better yield for SLS detection are the imaging techniques (chest x-ray and high-resolution computed tomography) along with pulmonary and diaphragmatic function tests. Evaluation of diaphragm dome motion by M-mode ultrasonography and phrenic nerve conduction studies are less useful. There are no standardized guidelines for the treatment of SLS in SLE. The majority of patients were treated with medium or high doses of glucocorticoids. Several immunosuppressive agents have been used in conjunction with steroids either if the patient fails to improve or since the beginning of the treatment. Theophylline and beta-agonists, alone or in combination with glucocorticoids, have been suggested with the intent to increase diaphragmatic strength. The overall long-term prognosis was good. The great majority of patients had significant clinical improvement and stabilization, or mild to moderate improvement on pulmonary function tests. The mortality rate was very low. PMID:27537601

Interactions between active pharmaceutical ingredients and excipients affecting bioavailability: impact on bioequivalence.

PubMed

García-Arieta, Alfredo

2014-12-18

The aim of the present paper is to illustrate the impact that excipients may have on the bioavailability of drugs and to review existing US-FDA, WHO and EMA regulatory guidelines on this topic. The first examples illustrate that small amounts of sorbitol (7, 50 or 60mg) affect the bioavailability of risperidone, a class I drug, oral solution, in contrast to what is stated in the US-FDA guidance. Another example suggests, in contrast to what is stated in the US-FDA BCS biowaivers guideline, that a small amount of sodium lauryl sulphate (SLS) (3.64mg) affects the bioavailability of risperidone tablets, although the reference product also includes SLS in an amount within the normal range for that type of dosage form. These factors are considered sufficient to ensure that excipients do not affect bioavailability according to the WHO guideline. The alternative criterion, defined in the WHO guideline and used in the FIP BCS biowaivers monographs, that asserts that excipients present in generic products of the ICH countries do not affect bioavailability if used in normal amounts, is shown to be incorrect with an example of alendronate (a class III drug) tablets, where 4mg of SLS increases bioavailability more than 5-fold, although a generic product in the USA contains SLS. Finally, another example illustrates that a 2mg difference in SLS may affect bioavailability of a generic product of a class II drug, even if SLS is contained in the comparator product, and in all cases its amount was within the normal range. Therefore, waivers of in vivo bioequivalence studies (e.g., BCS biowaivers, waivers of certain dosage forms in solution at the time of administration and variations in the excipient composition) should be assessed more cautiously. Copyright © 2014 Elsevier B.V. All rights reserved.

NASA's Space Launch System: An Evolving Capability for Exploration An Evolving Capability for Exploration

NASA Technical Reports Server (NTRS)

Creech, Stephen D.; Crumbly, Christopher M.; Robinson, Kimerly F.

2016-01-01

A foundational capability for international human deep-space exploration, NASA's Space Launch System (SLS) vehicle represents a new spaceflight infrastructure asset, creating opportunities for mission profiles and space systems that cannot currently be executed. While the primary purpose of SLS, which is making rapid progress towards initial launch readiness in two years, will be to support NASA's Journey to Mars, discussions are already well underway regarding other potential utilization of the vehicle's unique capabilities. In its initial Block 1 configuration, capable of launching 70 metric tons (t) to low Earth orbit (LEO), SLS is capable of propelling the Orion crew vehicle to cislunar space, while also delivering small CubeSat-class spacecraft to deep-space destinations. With the addition of a more powerful upper stage, the Block 1B configuration of SLS will be able to deliver 105 t to LEO and enable more ambitious human missions into the proving ground of space. This configuration offers opportunities for launching co-manifested payloads with the Orion crew vehicle, and a class of secondary payloads, larger than today's CubeSats. Further upgrades to the vehicle, including advanced boosters, will evolve its performance to 130 t in its Block 2 configuration. Both Block 1B and Block 2 also offer the capability to carry 8.4- or 10-m payload fairings, larger than any contemporary launch vehicle. With unmatched mass-lift capability, payload volume, and C3, SLS not only enables spacecraft or mission designs currently impossible with contemporary EELVs, it also offers enhancing benefits, such as reduced risk, operational costs and/or complexity, shorter transit time to destination or launching large systems either monolithically or in fewer components. This paper will discuss both the performance and capabilities of Space Launch System as it evolves, and the current state of SLS utilization planning.

NASA's Space Launch System: One Vehicle, Many Destinations

NASA Technical Reports Server (NTRS)

May, Todd A.; Creech, Stephen D.

2013-01-01

The National Aeronautics and Space Administration's (NASA) Space Launch System (SLS) Program, managed at the Marshall Space Flight Center, is making progress toward delivering a new capability for exploration beyond Earth orbit (BEO). Developed with the goals of safety, affordability and sustainability in mind, SLS will start with 10 percent more thrust than the Saturn V rocket that launched astronauts to the Moon 40 years ago. From there it will evolve into the most powerful launch vehicle ever flown, via an upgrade approach that will provide building blocks for future space exploration and development. The International Space Exploration Coordination Group, representing 12 of the world's space agencies, has worked together to create the Global Exploration Roadmap, which outlines paths towards a human landing on Mars, beginning with capability-demonstrating missions to the Moon or an asteroid. The Roadmap and corresponding NASA research outline the requirements for reference missions for all three destinations. This paper will explore the requirements needed for missions to BEO destinations, and the capability of SLS to meet those requirements and enable those missions. It will explain how NASA will execute this development within flat budgetary guidelines by using existing engines assets and heritage technology, from the initial 70 metric ton (t) lift capability through a block upgrade approach to an evolved 130-t capability. The SLS will offer a robust way to transport international crews and the air, water, food, and equipment they would need for extended trips to asteroids, the Moon, and Mars. In addition, this paper will detail SLS's capability to support missions beyond the human exploration roadmap, including robotic precursor missions to other worlds or uniquely high-mass space operation facilities in Earth orbit. As this paper will explain, the SLS provides game-changing mass and volume lift capability that makes it enhancing or enabling for a variety of unprecedented human and robotic missions.

NASA's Space Launch System: Development and Progress

NASA Technical Reports Server (NTRS)

Honeycutt, John; Lyles, Garry

2016-01-01

NASA is embarked on a new era of space exploration that will lead to new capabilities, new destinations, and new discoveries by both human and robotic explorers. Today, the International Space Station (ISS), supported by NASA's commercial partners, and robotic probes, are yielding knowledge that will help make this exploration possible. NASA is developing both the Orion crew vehicle and the Space Launch System (SLS) that will carry out a series of increasingly challenging missions that will eventually lead to human exploration of Mars. This paper will discuss the development and progress on the SLS. The SLS architecture was designed to be safe, affordable, and sustainable. The current configuration is the result of literally thousands of trade studies involving cost, performance, mission requirements, and other metrics. The initial configuration of SLS, designated Block 1, will launch a minimum of 70 metric tons (t) into low Earth orbit - significantly greater capability than any current launch vehicle. It is designed to evolve to a capability of 130 t through the use of upgraded main engines, advanced boosters, and a new upper stage. With more payload mass and volume capability than any rocket in history, SLS offers mission planners larger payloads, faster trip times, simpler design, shorter design cycles, and greater opportunity for mission success. Since the program was officially created in fall 2011, it has made significant progress toward first launch readiness of the Block 1 vehicle in 2018. Every major element of SLS continued to make significant progress in 2015. The Boosters element fired Qualification Motor 1 (QM-1) in March 2015, to test the 5-segment motor, including new insulation, joint, and propellant grain designs. The Stages element marked the completion of more than 70 major components of test article and flight core stage tanks. The Liquid Engines element conducted seven test firings of an RS-25 engine under SLS conditions. The Spacecraft/Payload Integration and Evolution element marked completion of the upper stage test article. Major work continues in 2016 as the program continues both flight and development RS-25 engine testing, begins welding test article and flight core stage tanks, completes stage adapter manufacturing, and test fires the second booster qualification motor. This paper will discuss the program's key accomplishments to date and the challenging work ahead for what will be the world's most capable launch vehicle.

NASA's SPACE LAUNCH SYSTEM: Development and Progress

NASA Technical Reports Server (NTRS)

Honeycutt, John; Lyles, Garry

2016-01-01

NASA is embarked on a new era of space exploration that will lead to new capabilities, new destinations, and new discoveries by both human and robotic explorers. Today, the International Space Station (ISS) and robotic probes are yielding knowledge that will help make this exploration possible. NASA is developing both the Orion crew vehicle and the Space Launch System (SLS) (Figure 1), that will carry out a series of increasingly challenging missions leading to human exploration of Mars. This paper will discuss the development and progress on the SLS. The SLS architecture was designed to be safe, affordable, and sustainable. The current configuration is the result of literally thousands of trade studies involving cost, performance, mission requirements, and other metrics. The initial configuration of SLS, designated Block 1, will launch a minimum of 70 metric tons (mT) (154,324 pounds) into low Earth orbit - significantly greater capability than any current launch vehicle. It is designed to evolve to a capability of 130 mT (286,601 pounds) through the use of upgraded main engines, advanced boosters, and a new upper stage. With more payload mass and volume capability than any existing rocket, SLS offers mission planners larger payloads, faster trip times, simpler design, shorter design cycles, and greater opportunity for mission success. Since the program was officially created in fall 2011, it has made significant progress toward launch readiness in 2018. Every major element of SLS continued to make significant progress in 2015. Engineers fired Qualification Motor 1 (QM-1) in March 2015 to test the 5-segment motor, including new insulation, joint, and propellant grain designs. More than 70 major components of test article and flight hardware for the Core Stage have been manufactured. Seven test firings have been completed with an RS-25 engine under SLS operating conditions. The test article for the Interim Cryogenic Propulsion Stage (ICPS) has also been completed. Major work continues in 2016 as the program continues both flight and development RS-25 engine testing, begins welding test article and flight core stage tanks, completes stage adapter manufacturing, and test fires the second booster qualification motor. This paper will discuss the program's key accomplishments to date and the challenging work ahead for what will be the world's most capable launch vehicle.

NASA's Space Launch System: An Enabling Capability for Discovery

NASA Technical Reports Server (NTRS)

Creech, Stephen D.

2014-01-01

The National Aeronautics and Space Administration's (NASA's) Space Launch System (SLS) Program, managed at the Marshall Space Flight Center, is making progress toward delivering a new capability for human spaceflight and scientific missions beyond Earth orbit. Developed with the goals of safety, affordability, and sustainability in mind, the SLS rocket will launch the Orion Multi-Purpose Crew Vehicle (MPCV), equipment, supplies, and major science missions for exploration and discovery. Making its first uncrewed test flight in 2017 and its first crewed flight in 2021, the SLS will evolve into the most powerful launch vehicle ever flown, capable of supporting human missions into deep space and to Mars. This paper will summarize the planned capabilities of the vehicle, the progress the SLS Program has made in the years since the Agency formally announced its architecture in September 2011, and the path the program is following to reach the launch pad in 2017 and then to evolve the 70 metric ton (t) initial lift capability to 130 t lift capability. The paper will outline the milestones the program has already reached, from developmental milestones such as the manufacture of the first flight hardware and recordbreaking engine testing, to life-cycle milestones such as the vehicle's Preliminary Design Review in the summer of 2013. The paper will also discuss the remaining challenges in both delivering the 70 t vehicle and in evolving its capabilities to the 130 t vehicle, and how the program plans to accomplish these goals. In addition, this paper will demonstrate how the Space Launch System is being designed to enable or enhance not only human exploration missions, but robotic scientific missions as well. Because of its unique launch capabilities, SLS will support simplifying spacecraft complexity, provide improved mass margins and radiation mitigation, and reduce mission durations. These capabilities offer attractive advantages for ambitious science missions by reducing infrastructure requirements, cost, and schedule. A traditional baseline approach for a mission to investigate the Jovian system would require a complicated trajectory with several gravity-assist planetary fly-bys to achieve the necessary outbound velocity. The SLS rocket, offering significantly higher C3 energies, can more quickly and effectively take the mission directly to its destination, providing scientific results sooner and at lower operational cost. The SLS rocket will launch payloads of unprecedented mass and volume, such as "monolithic" telescopes and in-space infrastructure, and will revolutionize science mission planning and design for years to come. As this paper will explain, SLS is making measurable progress toward becoming a global infrastructure asset for robotic and human scouts of all nations by harnessing business and technological innovations to deliver sustainable solutions for space exploration.

NASA'S Space Launch System: Progress Toward the Proving Ground

NASA Technical Reports Server (NTRS)

Jackman, Angie; Johnson, Les

2017-01-01

With significant and substantial progress being accomplished toward readying the Space Launch System (SLS) rocket for its first test flight, work is already also underway on preparations for the second flight – using an upgraded version of the vehicle – and beyond. Designed to support human missions into deep space, Space Launch System (SLS), is the most powerful human-rated launch vehicle the United States has ever undertaken, and together with the Orion spacecraft will support human exploration missions into the proving ground of cislunar space and ultimately to Mars. For its first flight, SLS will deliver a near-term heavy-lift capability for the nation with its 70-metric-ton Block 1 configuration. Each element of the vehicle now has flight hardware in production in support of the initial flight of the SLS, which will propel Orion around the moon and back. For its second flight, SLS will be upgraded to the more-capable Block 1B configuration. While the Block 1 configuration is capable of delivering more than 70 metric tons to low Earth orbit, the Block 1B vehicle will increase that capability to 105 metric tons. For that flight, the new configuration introduces two major new elements to the vehicle – an Exploration Upper Stage (EUS) that will be used for both ascent and in-space propulsion, and a Universal Stage Adapter (USA) that serves as a “payload bay” for the rocket, allowing the launch of large exploration systems along with the Orion spacecraft. Already, flight hardware is being prepared for the Block 1B vehicle. Beyond the second flight, additional upgrades will be made to the vehicle. The Block 1B vehicle will also be able to launch 8.4-meter-diameter payload fairings, larger than any previously flown, and the Spacecraft Payload Integration and Evolution (SPIE) Element will oversee development and production of those fairings. Ultimately, SLS will be evolved to a Block 2 configuration, which will replace the solid rocket boosters on the Block 1 and 1B vehicles with more powerful boosters, and will be capable of delivering at least 130 metric tons to LEO. The Block 2 vehicle will be capable of launching even larger 10-meter diameter fairings, which will enable human mission of Mars. With these fairings, the Block 1B and 2 configurations of SLS will also be enabling for a wide variety of other payloads. For robotic science probes to the outer solar system, for example, SLS can cut transit times to less than half that of currently available vehicles, producing earlier data return, enhancing iterative exploration, and reducing mission cost and risk. In the field of astrophysics, SLS’ high payload volume, in the form of payload fairings with a diameter of up to 10 meters, creates the opportunity for launch of large-aperture telescopes providing an unprecedented look at our universe, and offers the ability to conduct crewed servicing missions to observatories stationed at locations beyond low Earth orbit. This paper will provide a description of the SLS vehicle, and an overview of the vehicle’s capabilities and utilization potential.

The role of the potato (Solanum tuberosum) CCD8 gene in stolon and tuber development.

PubMed

Pasare, Stefania A; Ducreux, Laurence J M; Morris, Wayne L; Campbell, Raymond; Sharma, Sanjeev K; Roumeliotis, Efstathios; Kohlen, Wouter; van der Krol, Sander; Bramley, Peter M; Roberts, Alison G; Fraser, Paul D; Taylor, Mark A

2013-06-01

· Strigolactones (SLs) are a class of phytohormones controlling shoot branching. In potato (Solanum tuberosum), tubers develop from underground stolons, diageotropic stems which originate from basal stem nodes. As the degree of stolon branching influences the number and size distribution of tubers, it was considered timely to investigate the effects of SL production on potato development and tuber life cycle. · Transgenic potato plants were generated in which the CAROTENOID CLEAVAGE DIOXYGENASE8 (CCD8) gene, key in the SL biosynthetic pathway, was silenced by RNA interference (RNAi). · The resulting CCD8-RNAi potato plants showed significantly more lateral and main branches than control plants, reduced stolon formation, together with a dwarfing phenotype and a lack of flowering in the most severely affected lines. New tubers were formed from sessile buds of the mother tubers. The apical buds of newly formed transgenic tubers grew out as shoots when exposed to light. In addition, we found that CCD8 transcript levels were rapidly downregulated in tuber buds by the application of sprout-inducing treatments. · These results suggest that SLs could have an effect, solely or in combination with other phytohormones, in the morphology of potato plants and also in controlling stolon development and maintaining tuber dormancy. © 2013 The Authors. New Phytologist © 2013 New Phytologist Trust.

The SLS Stages Intertank Structural Test Assembly (STA) arrives at MSFC

NASA Image and Video Library

2018-03-06

The SLS Stages Intertank Structural Test Assembly (STA) is rolling off the NASA Pegasus Barge at the MSFC Dock enroute to the MSFC 4619 Load Test Annex test facility for qualification testing. Members of MSFC Logistics Office and Move Team members gather for last minute instructions and safety briefing before off-loading STA hardware.

WWC Review of the Report "Same-Language-Subtitling (SLS): Using Subtitled Music Video for Reading Growth". What Works Clearinghouse Single Study Review

ERIC Educational Resources Information Center

What Works Clearinghouse, 2013

2013-01-01

This randomized controlled trial examined the impacts of "Same-Language-Subtitling" ("SLS"), a karaoke-style subtitling intervention, on the reading comprehension skills of secondary school students in Kaneohe, Hawaii. Researchers randomly assigned 198 secondary school students with learning disabilities (ages 14 to 19) to…

Vehicle Support Posts Installation onto Mobile Launcher

NASA Image and Video Library

2017-05-25

Construction workers on the deck of the mobile launcher at NASA's Kennedy Space Center in Florida, prepare to install a vehicle support post. A total of eight support posts are being installed to support the load of the Space Launch System's (SLS) solid rocket boosters, with four posts for each of the boosters. The support posts are about five feet tall and each weigh about 10,000 pounds. The posts will structurally support the SLS rocket through T-0 and liftoff, and will drop down before vehicle liftoff to avoid contact with the flight hardware. The Ground Systems Development and Operations Program is overseeing installation of the support posts to prepare for the launch of the Orion spacecraft atop the SLS rocket.

Vehicle Support Posts Installation onto Mobile Launcher

NASA Image and Video Library

2017-05-25

At NASA's Kennedy Space Center in Florida, construction workers on the deck of the mobile launcher install the final four vehicle support posts. A total of eight support posts are being installed to support the load of the Space Launch System's (SLS) solid rocket boosters, with four posts for each of the boosters. The support posts are about five feet tall and each weigh about 10,000 pounds. The posts will structurally support the SLS rocket through T-0 and liftoff, and will drop down before vehicle liftoff to avoid contact with the flight hardware. The Ground Systems Development and Operations Program is overseeing installation of the support posts to prepare for the launch of the Orion spacecraft atop the SLS rocket.

Vehicle Support Posts Installation onto Mobile Launcher

NASA Image and Video Library

2017-05-25

At NASA's Kennedy Space Center in Florida, the final four vehicle support posts are being installed on the deck of the mobile launcher. A total of eight support posts are being installed to support the load of the Space Launch System's (SLS) solid rocket boosters, with four posts for each of the boosters. The support posts are about five feet tall and each weigh about 10,000 pounds. The posts will structurally support the SLS rocket through T-0 and liftoff, and will drop down before vehicle liftoff to avoid contact with the flight hardware. The Ground Systems Development and Operations Program is overseeing installation of the support posts to prepare for the launch of the Orion spacecraft atop the SLS rocket.

Vehicle Support Posts Installation onto Mobile Launcher

NASA Image and Video Library

2017-05-11

Construction workers on the deck of the mobile launcher at NASA's Kennedy Space Center in Florida, prepare a platform for installation of a vehicle support post. A total of eight support posts will be installed to support the load of the Space Launch System's (SLS) solid rocket boosters, with four posts for each of the boosters. The support posts are about five feet tall and each weigh about 10,000 pounds. The posts will structurally support the SLS rocket through T-0 and liftoff, and will drop down before vehicle liftoff to avoid contact with the flight hardware. The Ground Systems Development and Operations Program is overseeing installation of the support posts to prepare for the launch of the Orion spacecraft atop the SLS rocket.

Vehicle Support Posts Installation onto Mobile Launcher

NASA Image and Video Library

2017-05-11

A vehicle support post will lifted up by crane and lowered onto the deck of the mobile launcher at NASA's Kennedy Space Center in Florida. A total of eight support posts will be installed to support the load of the Space Launch System's (SLS) solid rocket boosters, with four posts for each of the boosters. The support posts are about five feet tall and each weigh about 10,000 pounds. The posts will structurally support the SLS rocket through T-0 and liftoff, and will drop down before vehicle liftoff to avoid contact with the flight hardware. The Ground Systems Development and Operations Program is overseeing installation of the support posts to prepare for the launch of the Orion spacecraft atop the SLS rocket.

Vehicle Support Posts Installation onto Mobile Launcher

NASA Image and Video Library

2017-05-11

In view are three vehicle support posts installed on the deck of the mobile launcher at NASA's Kennedy Space Center in Florida. A total of eight support posts will be installed to support the load of the Space Launch System's (SLS) solid rocket boosters, with four posts for each of the boosters. The support posts are about five feet tall and each weigh about 10,000 pounds. The posts will structurally support the SLS rocket through T-0 and liftoff, and will drop down before vehicle liftoff to avoid contact with the flight hardware. The Ground Systems Development and Operations Program is overseeing installation of the support posts to prepare for the launch of the Orion spacecraft atop the SLS rocket.

SSC-20170608-Journey Band Member Tours Stennis

NASA Image and Video Library

2017-06-08

Ross Valory, bass guitar player with the Rock and Roll Hall of Fame band Journey, visited NASA’s Stennis Space Center on June 8. Valory, along with several members of their crew, toured various facilities at Stennis including the B-2 Test Stand which will be used to test the core stage for NASA’s Space Launch System or SLS. The SLS is a powerful, advanced launch vehicle for a new era of human exploration beyond Earth’s orbit. With its unprecedented power and capabilities, SLS will launch crews of up to four astronauts in the agency’s Orion spacecraft on missions to explore multiple, deep-space destinations eventually including Mars. During the tour, Valory made this short video about America’s journey to Mars.

SRB Processing Facilities Media Event

NASA Image and Video Library

2016-03-01

Inside the Booster Fabrication Facility (BFF) at NASA’s Kennedy Space Center in Florida, members of the news media view the right-hand aft skirt that will be used on a solid rocket booster for NASA’s Space Launch System (SLS) rocket. Orbital ATK is contractor for NASA’s Marshall Space Flight Center in Alabama, and operates the BFF to prepare aft booster segments and hardware for the SLS solid rocket boosters. At far right, in the royal blue shirt, Rick Serfozo, Orbital ATK Florida site director, talks to the media. The SLS rocket and Orion spacecraft will launch on Exploration Mission-1 in 2018. The Ground Systems Development and Operations Program is preparing the infrastructure to process and launch spacecraft for deep-space missions and the journey to Mars.

Interim Cryogenic Propulsion Stage (ICPS) Transport from DOC to

NASA Image and Video Library

2017-07-26

The Interim Cryogenic Propulsion Stage (ICPS) for NASA's Space Launch System (SLS) rocket is packed inside a canister and ready to exit the United Launch Alliance (ULA) Delta Operations Center near Space Launch Complex 37 at Cape Canaveral Air Force Station for its move to the Space Station Processing Facility at NASA's Kennedy Space Center in Florida. The ICPS is the first integrated piece of flight hardware to arrive for the SLS. It is the in-space stage that is located toward the top of the rocket, between the Launch Vehicle Stage Adapter and the Orion Spacecraft Adapter. It will provide some of the in-space propulsion during Orion's first flight test atop the SLS on Exploration Mission-1.

Platform C South Arrival

NASA Image and Video Library

2016-08-04

A heavy load transport truck from Tillett Heavy Hauling in Titusville, Florida, arrives at the Vehicle Assembly Building (VAB) at NASA’s Kennedy Space Center in Florida, carrying a section of the first half of the C-level work platforms, C South, for the agency’s Space Launch System (SLS) rocket. The platform is being lifted and transferred onto support stands in the VAB staging area in the west parking lot. The Ground Systems Development and Operations Program is overseeing upgrades and modifications to VAB High Bay 3 to support processing of the SLS and Orion spacecraft. A total of 10 levels of new platforms, 20 platform halves altogether, will surround the SLS rocket and Orion spacecraft and provide access for testing and processing.

Space Launch System Spacecraft/Payloads Integration and Evolution Office Advanced Development FY 2014 Annual Report

NASA Technical Reports Server (NTRS)

Crumbly, C. M.; Bickley, F. P.; Hueter, U.

2015-01-01

The Advanced Development Office (ADO), part of the Space Launch System (SLS) program, provides SLS with the advanced development needed to evolve the vehicle from an initial Block 1 payload capability of 70 metric tons (t) to an eventual capability Block 2 of 130 t, with intermediary evolution options possible. ADO takes existing technologies and matures them to the point that insertion into the mainline program minimizes risk. The ADO portfolio of tasks covers a broad range of technical developmental activities. The ADO portfolio supports the development of advanced boosters, upper stages, and other advanced development activities benefiting the SLS program. A total of 36 separate tasks were funded by ADO in FY 2014.

Performance of the Research Animal Holding Facility (RAHF) and General Purpose Work Station (GPWS) and other hardware in the microgravity environment

NASA Technical Reports Server (NTRS)

Hogan, Robert P.; Dalton, Bonnie P.

1991-01-01

This paper discusses the performance of the Research Animal Holding Facility (RAHF) and General Purpose Work Station (GPWS) plus other associated hardware during the recent flight of Spacelab Life Sciences 1 (SLS-1). The RAHF was developed to provide proper housing (food, water, temperature control, lighting and waste management) for up to 24 rodents during flights on the Spacelab. The GPWS was designed to contain particulates and toxic chemicals generated during plant and animal handling and dissection/fixation activities during space flights. A history of the hardware development involves as well as the redesign activities prior to the actual flight are discussed.

Stratum corneum profiles of inflammatory mediators in patch test reactions to common contact allergens and sodium lauryl sulfate.

PubMed

Koppes, S A; Ljubojevic Hadzavdic, S; Jakasa, I; Franceschi, N; Jurakić Tončić, R; Marinović, B; Brans, R; Gibbs, S; Frings-Dresen, M H W; Rustemeyer, T; Kezic, S

2017-06-01

Recent studies have demonstrated allergen-specific differences in the gene expression of inflammatory mediators in patch tested skin. To determine levels of various inflammatory mediators in the stratum corneum (SC) after patch testing with common contact allergens and the skin irritant sodium lauryl sulfate (SLS). In total, 27 individuals who had previously patch tested positive to nickel, chromium, methylchloroisothiazolinone/methylisothiazolinone (MCI/MI) or para-phenylenediamine were retested and then patch tested with SLS and petrolatum, with petrolatum serving as the patch test control. At 72 h, the test sites were clinically graded and the SC samples collected on adhesive tape. The levels of 18 of the 32 quantified mediators differed significantly from that of the control patches for at least one of the tested substances. SLS and MCI/MI induced the largest number of immunomediators. Interleukin (IL)-16 levels were significantly higher in patch test reactions in all allergens than they were in the controls, while no significant difference was detected for SLS. Furthermore, a strong negative correlation was found between strength of patch test reaction and IL-1α levels. Cytokine profiles in the SC of patch tested skin did not show a distinct allergen-specific pattern. However, MCI/MI induced a larger and wider immune response than the other allergens, perhaps due to its potency as an irritant. The levels of IL-16 were significantly increased in patch test reactions to allergens but not to SLS; thus, they may help clinicians to differentiate between allergic contact dermatitis and irritant contact dermatitis. © 2016 British Association of Dermatologists.

Sodium lauryl sulfate-induced irritation in the human face: regional and age-related differences.

PubMed

Marrakchi, S; Maibach, H I

2006-01-01

The particular sensitivity of the human face to care products prompted us to study irritation induced by sodium lauryl sulfate (SLS) in its various regions. We examined regional and age-related differences, correlating basal transepidermal water loss (TEWL) and capacitance to SLS irritation. SLS (2% aq.) was applied under occlusion for 1 h to the forehead, cheek, nose, nasolabial and perioral areas, chin, neck and forearm to two groups of subjects--one with 10 subjects with an average age of 25.2 +/- 4.7 years and another with 10 subjects with an average age of 73.7 +/- 3.9 years. TEWL was measured before and 1 h and 23 h after patch removal. Baseline stratum corneum hydration was also measured. Irritation was assessed by the changes in TEWL (deltaTEWL = TEWL after patch removal - basal TEWL) after corrections to the control. In the younger group, all areas of the face and the neck reacted to SLS, whereas the forearm did not. In the older group, the nose, perioral area and forearm did not react. In both age groups, some significant differences between the regions of the face were detected. The younger group showed higher changes in TEWL than the older group in all the areas studied, but only in the chin and nasolabial area were the differences statistically significant. Significant correlations were found between basal TEWL and deltaTEWL in 5 of the 7 areas which reacted to SLS. Baseline TEWL is one parameter that correlates with the susceptibility of the face to this irritant. 2006 S. Karger AG, Basel

Using NASA's Space Launch System to Enable Game Changing Science Mission Designs

NASA Technical Reports Server (NTRS)

Creech, Stephen D.

2013-01-01

NASA's Marshall Space Flight Center is directing efforts to build the Space Launch System (SLS), a heavy-lift rocket that will help restore U.S. leadership in space by carrying the Orion Multi-Purpose Crew Vehicle and other important payloads far beyond Earth orbit. Its evolvable architecture will allow NASA to begin with Moon fly-bys and then go on to transport humans or robots to distant places such as asteroids, Mars, and the outer solar system. Designed to simplify spacecraft complexity, the SLS rocket will provide improved mass margins and radiation mitigation, and reduced mission durations. These capabilities offer attractive advantages for ambitious missions such as a Mars sample return, by reducing infrastructure requirements, cost, and schedule. For example, if an evolved expendable launch vehicle (EELV) were used for a proposed mission to investigate the Saturn system, a complicated trajectory would be required with several gravity-assist planetary fly-bys to achieve the necessary outbound velocity. The SLS rocket, using significantly higher C3 energies, can more quickly and effectively take the mission directly to its destination, reducing trip times and cost. As this paper will report, the SLS rocket will launch payloads of unprecedented mass and volume, such as monolithic telescopes and in-space infrastructure. Thanks to its ability to co-manifest large payloads, it also can accomplish complex missions in fewer launches. Future analyses will include reviews of alternate mission concepts and detailed evaluations of SLS figures of merit, helping the new rocket revolutionize science mission planning and design for years to come.

Complex Decision-Making Applications for the NASA Space Launch System

NASA Technical Reports Server (NTRS)

Lyles, Garry; Flores, Tim; Hundley, Jason; Monk, Timothy; Feldman, Stuart

2012-01-01

The Space Shuttle program is ending and elements of the Constellation Program are either being cancelled or transitioned to new NASA exploration endeavors. NASA is working diligently to select an optimum configuration for the Space Launch System (SLS), a heavy lift vehicle that will provide the foundation for future beyond LEO large ]scale missions for the next several decades. Thus, multiple questions must be addressed: Which heavy lift vehicle will best allow the agency to achieve mission objectives in the most affordable and reliable manner? Which heavy lift vehicle will allow for a sufficiently flexible exploration campaign of the solar system? Which heavy lift vehicle configuration will allow for minimizing risk in design, test, build and operations? Which heavy lift vehicle configuration will be sustainable in changing political environments? Seeking to address these questions drove the development of an SLS decisionmaking framework. From Fall 2010 until Spring 2011, this framework was formulated, tested, fully documented, and applied to multiple SLS vehicle concepts at NASA from previous exploration architecture studies. This was a multistep process that involved performing FOM-based assessments, creating Pass/Fail gates based on draft threshold requirements, performing a margin-based assessment with supporting statistical analyses, and performing sensitivity analysis on each. This paper discusses the various methods of this process that allowed for competing concepts to be compared across a variety of launch vehicle metrics. The end result was the identification of SLS launch vehicle candidates that could successfully meet the threshold requirements in support of the SLS Mission Concept Review (MCR) milestone.

Complex Decision-Making Applications for the NASA Space Launch System

NASA Technical Reports Server (NTRS)

Lyles, Garry; Flores, Tim; Hundley, Jason; Feldman, Stuart; Monk, Timothy

2012-01-01

The Space Shuttle program is ending and elements of the Constellation Program are either being cancelled or transitioned to new NASA exploration endeavors. The National Aeronautics and Space Administration (NASA) has worked diligently to select an optimum configuration for the Space Launch System (SLS), a heavy lift vehicle that will provide the foundation for future beyond low earth orbit (LEO) large-scale missions for the next several decades. Thus, multiple questions must be addressed: Which heavy lift vehicle will best allow the agency to achieve mission objectives in the most affordable and reliable manner? Which heavy lift vehicle will allow for a sufficiently flexible exploration campaign of the solar system? Which heavy lift vehicle configuration will allow for minimizing risk in design, test, build and operations? Which heavy lift vehicle configuration will be sustainable in changing political environments? Seeking to address these questions drove the development of an SLS decision-making framework. From Fall 2010 until Spring 2011, this framework was formulated, tested, fully documented, and applied to multiple SLS vehicle concepts at NASA from previous exploration architecture studies. This was a multistep process that involved performing figure of merit (FOM)-based assessments, creating Pass/Fail gates based on draft threshold requirements, performing a margin-based assessment with supporting statistical analyses, and performing sensitivity analysis on each. This paper discusses the various methods of this process that allowed for competing concepts to be compared across a variety of launch vehicle metrics. The end result was the identification of SLS launch vehicle candidates that could successfully meet the threshold requirements in support of the SLS Mission Concept Review (MCR) milestone.

STS-58 crewmembers participate in baseline data collection

NASA Image and Video Library

1993-09-29

S93-45370 (29 Sept 1993) --- Blood samples from crew members are critical to several Spacelab Life Sciences (SLS-2) investigations. Amalour Veloso (left) and Sandra Prow draw blood from David A. Wolf, mission specialist. Wolf was participating with five other NASA astronauts and a payload specialist on data collection and training in preparation for the two week SLS-2 mission.

SRB Stack Training

NASA Image and Video Library

2018-01-30

Crane operators and ground support personnel practice lifting and stacking mock-ups of solid rocket booster (SRB) segments in High Bay 4 inside the Vehicle Assembly Building at NASA’s Kennedy Space Center in Florida. The training will help workers prepare for SRB stacking operations for the agency's Space Launch System SLS) rocket. The SLS will launch the Orion spacecraft on its first integrated flight, Exploration Mission-1.

The SLS Stages Intertank Structural Test Assembly (STA) arrives at MSFC

NASA Image and Video Library

2018-03-08

The SLS Stages Intertank Structural Test Assembly (STA) is rolling off the NASA Pegasus Barge at the MSFC Dock enroute to the MSFC 4619 Load Test Annex test facility for qualification testing via MSFC West Test Area. STA enters West Test Area from intersection of Dodd and Saturn roads. Onlookers take photos with Historic Dynamic Test Stand in background.

The Stafford Student Loan Program. Testimony before the Subcommittee on Permanent Investigations, Committee on Governmental Affairs, United States Senate.

ERIC Educational Resources Information Center

Frazier, Franklin

The Stafford Loan Program (formerly called the Guaranteed Student Loan Program) makes three kinds of student loans for postsecondary education: Stafford Loans, Supplemental Loans for Students (SLS), and Parents Loans for Undergraduate Students (PLUS). Stafford loans are low-interest loans based on financial need, while SLS and PLUS loans are not…

Organic Binder Developments for Solid Freeform Fabrication

NASA Technical Reports Server (NTRS)

Cooper, Ken; Mobasher, Amir A.

2003-01-01

A number of rapid prototyping techniques are under development at Marshall Space Flight Center's (MSFC) National Center for Advanced Manufacturing Rapid Prototyping Laboratory. Commercial binder developments in creating solid models for rapid prototyping include: 1) Fused Deposition Modeling; 2) Three Dimensional Printing; 3) Selective Laser Sintering (SLS). This document describes these techniques developed by the private sector, as well as SLS undertaken by MSFC.

STS-40 MS Seddon, wearing blindfold, sleeps in SLS-1 module

NASA Image and Video Library

1991-06-14

STS040-31-020 (5-14 June 1991) --- During the nine-day mission, some of the crew slept in the SLS-1 module. Astronaut Rhea Seddon, using various restraints, sleeps horizontally in this scene. The image was one of 25 visuals used by the STS-40 crew at its Post Flight Press Conference (PFPC) on June 28, 1991.

Space Life Sciences-2 (SLS-2) logo or patch

NASA Image and Video Library

1993-03-01

S93-26894 (March 1993) --- Spacelab Life Sciences 2, scheduled to fly as the major payload on the STS-58 mission, is represented with this logo. As in the case of SLS-1, which flew in space in June of 1991, this Spacelab mission will be devoted to life sciences and will carry a crew of experts in the associated disciplines.

Surfactant sodium lauryl sulfate enhances skin vaccination: molecular characterization via a novel technique using ultrafiltration capillaries and mass spectrometric proteomics.

PubMed

Huang, Chun-Ming; Wang, Chao-Cheng; Kawai, Mikako; Barnes, Stephen; Elmets, Craig A

2006-03-01

The skin is a highly accessible organ and thus provides an attractive immune environment for cost-effective, simple, and needle-free delivery of vaccines and immunomodulators. In this study, we pretreated mouse skin with an anionic surfactant, sodium lauryl sulfate (SLS), for a short period of time (10 min) followed by epicutaneous vaccination with hen egg lysozyme antigen. We demonstrated for the first time that pretreatment of skin with surfactant SLS significantly enhances the production of antibody to hen egg lysozyme. Short term pretreatment with SLS disorganized the stratum corneum, extracted partial lamellar lipids, induced the maturation of Langerhans cells, and did not result in epidermis thickening. To reveal the mechanism underlying these changes, particularly at the molecular level, we used a novel proteomic technique using ultrafiltration capillaries and mass spectrometry to identify in vivo proteins/peptides secreted in the SLS-pretreated skin. Two secretory proteins, named as calcium-binding protein S100A9 and thymosin beta4, were identified by this novel technique. These two proteins thus may provide new insight into the enhancing effect of surfactants on skin vaccination.

Chemical genetics and strigolactone perception

PubMed Central

Lumba, Shelley; Bunsick, Michael; McCourt, Peter

2017-01-01

Strigolactones (SLs) are a collection of related small molecules that act as hormones in plant growth and development. Intriguingly, SLs also act as ecological communicators between plants and mycorrhizal fungi and between host plants and a collection of parasitic plant species. In the case of mycorrhizal fungi, SLs exude into the soil from host roots to attract fungal hyphae for a beneficial interaction. In the case of parasitic plants, however, root-exuded SLs cause dormant parasitic plant seeds to germinate, thereby allowing the resulting seedling to infect the host and withdraw nutrients. Because a laboratory-friendly model does not exist for parasitic plants, researchers are currently using information gleaned from model plants like Arabidopsis in combination with the chemical probes developed through chemical genetics to understand SL perception of parasitic plants. This work first shows that understanding SL signaling is useful in developing chemical probes that perturb SL perception. Second, it indicates that the chemical space available to probe SL signaling in both model and parasitic plants is sizeable. Because these parasitic pests represent a major concern for food insecurity in the developing world, there is great need for chemical approaches to uncover novel lead compounds that perturb parasitic plant infections. PMID:28690842

Characterization of synthetic lung surfactant activity against proinflammatory cytokines in human monocytes.

PubMed

Otsubo, Eiji; Irimajiri, Kiyohiro; Takei, Tsunetomo; Nomura, Masato

2002-03-01

Our previous study demonstrated that the smallest synthetic peptide with the sequence CPVHLKRLLLLLLLLLLLLLLLL, SP-CL16(6-28), admixed with phospholipid (synthetic lung surfactant, SLS) showed strong surface activity. In this study, we attempted to develop a dual-type surfactant with both anti inflammatory and surface activities. SP-CL16(6-28) was first chemically synthesized and then purified for use by centrifugal partition chromatography. A mixture of SP-CL16(6-28) and phospholipid complex was tested for anti inflammatory activity using the human monocyte cell line THP-1. Whether the suppression of tumor necrosis factor-alpha (TNF-a), interleukin (IL)-8, IL-6, IL-1beta, and macrophage migration inhibitory factor (MIF) was reduced by lipopolysaccharide (LPS) in monocytes was examined. Levels of these cytokines were measured by enzyme-linked immunosorbent assay. It was found that SLS significantly and dose dependently inhibited the secretion of TNF-alpha by THP-1 cells following stimulation with LPS. Dipalmitoylphosphatidylcoline did not inhibit the release of cytokines. These findings suggest that SLS has anti inflammatory activity. Therefore it should be possible to develop a SLS with both anti inflammatory activity and surface activity.

Spacelab Life Science-1 Mission Onboard Photograph

NASA Technical Reports Server (NTRS)

1991-01-01

The laboratory module in the cargo bay of the Space Shuttle Orbiter Columbia was photographed during the Spacelab Life Science-1 (SLS-1) mission. SLS-1 was the first Spacelab mission dedicated solely to life sciences. The main purpose of the SLS-1 mission was to study the mechanisms, magnitudes, and time courses of certain physiological changes that occur during space flight, to investigate the consequences of the body's adaptation to microgravity and readjustment to Earth's gravity, and to bring the benefits back home to Earth. The mission was designed to explore the responses of the heart, lungs, blood vessels, kidneys, and hormone-secreting glands to microgravity and related body fluid shifts; examine the causes of space motion sickness; and study changes in the muscles, bones and cells. The five body systems being studied were: The Cardiovascular/Cardiopulmonary System (heart, lungs, and blood vessels), the Renal/Endocrine System (kidney and hormone-secreting organs), the Immune System (white blood cells), the Musculoskeletal System (muscles and bones), and the Neurovestibular System (brain and nerves, eyes, and irner ear). The SLS-1 was launched aboard the Space Shuttle Orbiter Columbia (STS-40) on June 5, 1995.

Fabrication and characterization of silk fibroin-coated liposomes for ocular drug delivery.

PubMed

Dong, Yixuan; Dong, Pin; Huang, Di; Mei, Liling; Xia, Yaowen; Wang, Zhouhua; Pan, Xin; Li, Ge; Wu, Chuanbin

2015-04-01

The unique structure and protective mechanisms of the eye result in low bioavailability of ocular drugs. Using a mucoadhesive material is an efficient solution to improve ocular drug therapeutic efficacy. This study was designed to prepare a liposomal formulation coated by a novel adhesive excipient, silk fibroin (SF), for topical ocular drug delivery. The regenerated silk fibroins (SFs) with different dissolving time were coated onto the ibuprofen-loaded liposomes. The morphology, drug encapsulation efficiency, in vitro release and in vitro corneal permeation of SF-coated liposomes (SLs) were investigated in comparison with the conventional liposome. Cellular adhesion and cytotoxicity assay of SF and SLs were tested using human corneal epithelial cells (HCEC). SLs showed sustained drug release and in vitro corneal permeation of ibuprofen as compared to drug solution and conventional liposome. The cellular fluorescence appeared after 7 min of exposure to SF, and the intensity increased sustainedly up to 12h with no detectable cytotoxicity. Higher fluorescence intensity of Nile red in SLs was observed in a short period of 15 min showing a rapid uptake. These favorable properties make SF-coated liposome be a promising ocular drug delivery system. Copyright © 2015 Elsevier B.V. All rights reserved.

NASA's Space Launch System: Progress Report

NASA Technical Reports Server (NTRS)

Cook, Jerry; Lyles, Garry

2017-01-01

After more than four decades exploring the space environment from low Earth orbit and developing long-duration spaceflight operational experience with the International Space Station (ISS), NASA is once again preparing to send explorers into deep space. Development, test and manufacturing is now underway on the launch vehicle, the crew spacecraft and the ground processing and launch facilities to support human and robotic missions to the moon, Mars and the outer solar system. The enabling launch vehicle for these ambitious new missions is the Space Launch System (SLS), managed by NASA's Marshall Space Flight Center (MSFC). Since the program began in 2011, the design has passed Critical Design Review, and extensive development, test and flight hardware has been produced by every major element of the SLS vehicle. Testing continues on engines, boosters, tanks and avionics. While the program has experienced engineering challenges typical of a new development, it continues to make steady progress toward the first SLS mission in roughly two years and a sustained cadence of missions thereafter. This paper will discuss these and other technical and SLS programmatic successes and challenges over the past year and provide a preview of work ahead before first flight.

3D printing of drug-loaded gyroid lattices using selective laser sintering.

PubMed

Fina, Fabrizio; Goyanes, Alvaro; Madla, Christine M; Awad, Atheer; Trenfield, Sarah J; Kuek, Jia Min; Patel, Pavanesh; Gaisford, Simon; Basit, Abdul W

2018-05-19

Three-dimensional printing (3DP) is gaining momentum in the field of pharmaceuticals, offering innovative opportunities for medicine manufacture. Selective laser sintering (SLS) is a novel, high resolution and single-step printing technology that we have recently introduced to the pharmaceutical sciences. The aim of this work was to use SLS 3DP to fabricate printlets (3D printed tablets) with cylindrical, gyroid lattice and bi-layer structures having customisable release characteristics. Paracetamol-loaded constructs from four different pharmaceutical grade polymers including polyethylene oxide, Eudragit (L100-55 and RL) and ethyl cellulose, were created using SLS 3DP. The novel gyroid lattice structure was able to modulate the drug release from all four polymers. This work is the first to demonstrate the feasibility of using SLS to achieve customised drug release properties of several polymers, in a swift, cost-effective manner, avoiding the need to alter the formulation composition. By creating these constructs, it is therefore possible to modify drug release, which in practice, could enable the tailoring of drug performance to the patient simply by changing the 3D design. Copyright © 2018 Elsevier B.V. All rights reserved.

Sesquiterpene lactones from the methanol extracts of twenty-eight Hieracium species from the Balkan Peninsula and their chemosystematic significance.

PubMed

Milutinović, Violeta; Niketić, Marjan; Krunić, Aleksej; Nikolić, Dejan; Petković, Miloš; Ušjak, Ljuboš; Petrović, Silvana

2018-06-20

Four sesquiterpene lactones (SLs), including three undescribed proline-SL conjugates, the guaianolides calophyllamine A and 8-epiixerisamine A, and the eudesmanolide calophyllamine B, were isolated from the methanol extract of Hieracium calophyllum R. Uechtr. (Compositae) flowering heads. Another known guaianolide, crepiside E, was detected in Hieracium L. species for the first time. Their structures were elucidated using extensive 1D and 2D NMR spectroscopy in combination with HRMS. The isolated SLs were used as external standards for qualitative and quantitative LC-MS analysis of the dry methanol extracts of the flowering aerial parts of 28 Hieracium species from the Balkan Peninsula. Guaianolides were the dominant SLs in 27 species studied. The chemosystematic significance of detected SLs was evaluated using multivariate statistics (PCA, nMDS and UPGMA). Differentiation between the main groups was well supported. All four compounds significantly and equally contributed to the differences between the species. In addition, the eudesmanolide calophyllamine B could be a significant chemosystematic marker for H. sect. Villosa (Griseb.) Gremli s.l. and Glauciformia (Freyn) Zahn-Italica (Fr.) Av. Touv. Copyright © 2018 Elsevier Ltd. All rights reserved.

Vehicle Support Posts Installation onto Mobile Launcher

NASA Image and Video Library

2017-05-11

A construction worker on the deck of the mobile launcher welds a portion of a platform for installation of a vehicle support post at NASA's Kennedy Space Center in Florida. A total of eight support posts will be installed to support the load of the Space Launch System's (SLS) solid rocket boosters, with four posts for each of the boosters. The support posts are about five feet tall and each weigh about 10,000 pounds. The posts will structurally support the SLS rocket through T-0 and liftoff, and will drop down before vehicle liftoff to avoid contact with the flight hardware. The Ground Systems Development and Operations Program is overseeing installation of the support posts to prepare for the launch of the Orion spacecraft atop the SLS rocket.

Influence of sodium lauryl sulfate and tween 80 on carbamazepine-nicotinamide cocrystal solubility and dissolution behaviour.

PubMed

Li, Mingzhong; Qiao, Ning; Wang, Ke

2013-10-11

The influence of the surfactants of sodium lauryl sulfate (SLS) and Tween 80 on carbamazepine-nicotinamide (CBZ-NIC) cocrystal solubility and dissolution behaviour has been studied in this work. The solubility of the CBZ-NIC cocrystal was determined by measuring the eutectic concentrations of the drug and the coformer. Evolution of the intrinsic dissolution rate (IDR) of the CBZ-NIC cocrystal was monitored by the UV imaging dissolution system during dissolution. Experimental results indicated that SLS and Tween 80 had little influence upon the solubility of the CBZ-NIC cocrystal but they had totally opposite effects on the IDR of the CBZ-NIC cocrystal during dissolution. SLS significantly increased the IDR of the CBZ-NIC cocrystal while Tween 80 decreased its IDR.

Influence of Sodium Lauryl Sulfate and Tween 80 on Carbamazepine–Nicotinamide Cocrystal Solubility and Dissolution Behaviour

PubMed Central

Li, Mingzhong; Qiao, Ning; Wang, Ke

2013-01-01

The influence of the surfactants of sodium lauryl sulfate (SLS) and Tween 80 on carbamazepine–nicotinamide (CBZ–NIC) cocrystal solubility and dissolution behaviour has been studied in this work. The solubility of the CBZ–NIC cocrystal was determined by measuring the eutectic concentrations of the drug and the coformer. Evolution of the intrinsic dissolution rate (IDR) of the CBZ–NIC cocrystal was monitored by the UV imaging dissolution system during dissolution. Experimental results indicated that SLS and Tween 80 had little influence upon the solubility of the CBZ–NIC cocrystal but they had totally opposite effects on the IDR of the CBZ–NIC cocrystal during dissolution. SLS significantly increased the IDR of the CBZ–NIC cocrystal while Tween 80 decreased its IDR. PMID:24300560

The NASA Space Launch System Program Systems Engineering Approach for Affordability

NASA Technical Reports Server (NTRS)

Hutt, John J.; Whitehead, Josh; Hanson, John

2017-01-01

The National Aeronautics and Space Administration is currently developing the Space Launch System to provide the United States with a capability to launch large Payloads into Low Earth orbit and deep space. One of the development tenets of the SLS Program is affordability. One initiative to enhance affordability is the SLS approach to requirements definition, verification and system certification. The key aspects of this initiative include: 1) Minimizing the number of requirements, 2) Elimination of explicit verification requirements, 3) Use of certified models of subsystem capability in lieu of requirements when appropriate and 4) Certification of capability beyond minimum required capability. Implementation of each aspect is described and compared to a "typical" systems engineering implementation, including a discussion of relative risk. Examples of each implementation within the SLS Program are provided.

Vehicle Support Posts Installation onto Mobile Launcher

NASA Image and Video Library

2017-05-11

Construction workers on the deck of the mobile launcher prepare the platforms for installation of vehicle support posts at NASA's Kennedy Space Center in Florida. At left, four of the support posts are installed. A total of eight support posts will be installed to support the load of the Space Launch System's (SLS) solid rocket boosters, with four posts for each of the boosters. The support posts are about five feet tall and each weigh about 10,000 pounds. The posts will structurally support the SLS rocket through T-0 and liftoff, and will drop down before vehicle liftoff to avoid contact with the flight hardware. The Ground Systems Development and Operations Program is overseeing installation of the support posts to prepare for the launch of the Orion spacecraft atop the SLS rocket.

Vehicle Support Posts Installation onto Mobile Launcher

NASA Image and Video Library

2017-05-11

Several heavy lift cranes surround the mobile launcher at NASA's Kennedy Space Center in Florida. Preparations are underway to lift a vehicle support post up and onto the mobile launcher for installation on the deck. A total of eight support posts will be installed to support the load of the Space Launch System's (SLS) solid rocket boosters, with four posts for each of the boosters. The support posts are about five feet tall and each weigh about 10,000 pounds. The posts will structurally support the SLS rocket through T-0 and liftoff, and will drop down before vehicle liftoff to avoid contact with the flight hardware. The Ground Systems Development and Operations Program is overseeing installation of the support posts to prepare for the launch of the Orion spacecraft atop the SLS rocket.

Cryogenic Propulsion Stage (CPS) Configuration in Support of NASA's Multiple Design Reference Missions (DRMs)

NASA Technical Reports Server (NTRS)

Hanna, Stephen G.; Jones, David L.; Creech, Stephen D.; Lawrence, Thomas D.

2012-01-01

In support of the National Aeronautics and Space Administration's (NASA) Human Exploration and Operations Mission Directorate (HEOMD), the Space Launch System (SLS) is being designed for safe, affordable, and sustainable human and scientific exploration missions beyond Earth's or-bit (BEO). The SLS Team is tasked with developing a system capable of safely and repeatedly lofting a new fleet of spaceflight vehicles beyond Earth orbit. The Cryogenic Propulsion Stage (CPS) is a key enabler for evolving the SLS capability for BEO missions. This paper reports on the methodology and initial recommendations relative to the CPS, giving a brief retrospective of early studies on this promising propulsion hardware. This paper provides an overview of the requirements development and CPS configuration in support of NASA's multiple Design Reference Missions (DRMs).

Preparing to Test for Deep Space

NASA Image and Video Library

2015-07-15

A structural steel section is lifted into place atop the B-2 Test Stand at NASA’s Stennis Space Center as part of modification work to prepare for testing the core stage of NASA’s new Space Launch System. The section is part of the Main Propulsion Test Article (MPTA) framework, which will support the SLS core stage for testing. The existing framework was installed on the stand in the late 1970s to test the shuttle MPTA. However, that framework had to be repositioned and modified to accommodate the larger SLS stage. About 1 million pounds of structural steel has been added, extending the framework about 100 feet higher and providing a new look to the Stennis skyline. Stennis will test the actual flight core stage for the first uncrewed SLS mission, Exploration Mission-1.

Enhancement of breakdown voltage for fully-vertical GaN-on-Si p-n diode by using strained layer superlattice as drift layer

NASA Astrophysics Data System (ADS)

Mase, Suguru; Hamada, Takeaki; Freedsman, Joseph J.; Egawa, Takashi

2018-06-01

We have demonstrated a vertical GaN-on-Si p-n diode with breakdown voltage (BV) as high as 839 V by using a low Si-doped strained layer superlattice (SLS). The p-n vertical diode fabricated by using the n‑-SLS layer as a part of the drift layer showed a remarkable enhancement in BV, when compared with the conventional n‑-GaN drift layer of similar thickness. The vertical GaN-on-Si p-n diodes with 2.3 μm-thick n‑-GaN drift layer and 3.0 μm-thick n‑-SLS layer exhibited a differential on-resistance of 4.0 Ω · cm2 and a BV of 839 V.

Spacelab Life Sciences 1, development towards successive life sciences flights

NASA Technical Reports Server (NTRS)

Dalton, B. P.; Jahns, G.; Hogan, R.

1992-01-01

A general review is presented of flight data and related hardware developments for Spacelab Life Sciences (SLS) 1 with an eye toward applying this knowledge to projected flight planning. Specific attention is given to the Research Animal Holding Facility (RAHF), the General Purpose Work Station (GPWS), the Small Mass Measuring Instrument (SMMI), and the Animal Enclosure Module (AEM). Preflight and in-flight testing methods are detailed including biocompatibility tests, parametric engineering sensitivity analyses, measurements of environmental parameters, and studies of operational interfaces. Particulate containment is demonstrated for some of the equipment, and successful use of the GPWS, RAHF, AEM, and SMMI are reported. The in-flight data are useful for developing more advanced hardware such as the AEM for SLS flight 2 and the modified RAHF for SLS flight 3.

Space Launch System Spacecraft and Payload Elements: Making Progress Toward First Launch

NASA Technical Reports Server (NTRS)

Schorr, Andrew A.; Creech, Stephen D.

2016-01-01

Significant and substantial progress continues to be accomplished in the design, development, and testing of the Space Launch System (SLS), the most powerful human-rated launch vehicle the United States has ever undertaken. Designed to support human missions into deep space, SLS is one of three programs being managed by the National Aeronautics and Space Administration's (NASA's) Exploration Systems Development directorate. The Orion spacecraft program is developing a new crew vehicle that will support human missions beyond low Earth orbit, and the Ground Systems Development and Operations program is transforming Kennedy Space Center into next-generation spaceport capable of supporting not only SLS but also multiple commercial users. Together, these systems will support human exploration missions into the proving ground of cislunar space and ultimately to Mars. SLS will deliver a near-term heavy-lift capability for the nation with its 70 metric ton (t) Block 1 configuration, and will then evolve to an ultimate capability of 130 t. The SLS program marked a major milestone with the successful completion of the Critical Design Review in which detailed designs were reviewed and subsequently approved for proceeding with full-scale production. This marks the first time an exploration class vehicle has passed that major milestone since the Saturn V vehicle launched astronauts in the 1960s during the Apollo program. Each element of the vehicle now has flight hardware in production in support of the initial flight of the SLS -- Exploration Mission-1 (EM-1), an un-crewed mission to orbit the moon and return. Encompassing hardware qualification, structural testing to validate hardware compliance and analytical modeling, progress in on track to meet the initial targeted launch date in 2018. In Utah and Mississippi, booster and engine testing are verifying upgrades made to proven shuttle hardware. At Michoud Assembly Facility in Louisiana, the world's largest spacecraft welding tool is producing tanks for the SLS core stage. This paper will particularly focus on work taking place at Marshall Space Flight Center (MSFC) and United Launch Alliance in Alabama, where upper stage and adapter elements of the vehicle are being constructed and tested. Providing the Orion crew capsule/launch vehicle interface and in-space propulsion via a cryogenic upper stage, the Spacecraft/Payload Integration and Evolution (SPIE) Element serves a key role in achieving SLS goals and objectives. The SPIE element marked a major milestone in 2014 with the first flight of original SLS hardware, the Orion Stage Adapter (OSA) which was used on Exploration Flight Test-1 with a design that will be used again on EM-1. Construction is already underway on the EM-1 Interim Cryogenic Propulsion Stage (ICPS), an in-space stage derived from the Delta Cryogenic Second Stage. Manufacture of the Orion Stage Adapter and the Launch Vehicle Stage Adapter is set to begin at the Friction Stir Facility located at MSFC while structural test articles are either completed (OSA) or nearing completion (Launch Vehicle Stage Adapter). An overview is provided of the launch vehicle capabilities, with a specific focus on SPIE Element qualification/testing progress, as well as efforts to provide access to deep space regions currently not available to the science community through a secondary payload capability utilizing CubeSat-class satellites.

Space Launch System Spacecraft and Payload Elements: Making Progress Toward First Launch

NASA Technical Reports Server (NTRS)

Schorr, Andrew A.; Creech, Stephen D.; Ogles, Michael; Hitt, David

2016-01-01

Significant and substantial progress continues to be accomplished in the design, development, and testing of the Space Launch System (SLS), the most powerful human-rated launch vehicle the United States has ever undertaken. Designed to support human missions into deep space, SLS is one of three programs being managed by the National Aeronautics and Space Administration's (NASA's) Exploration Systems Development directorate. The Orion spacecraft program is developing a new crew vehicle that will support human missions beyond low Earth orbit, and the Ground Systems Development and Operations (GSDO) program is transforming Kennedy Space Center (KSC) into next-generation spaceport capable of supporting not only SLS but also multiple commercial users. Together, these systems will support human exploration missions into the proving ground of cislunar space and ultimately to Mars. SLS will deliver a near-term heavy-lift capability for the nation with its 70 metric ton Block 1 configuration, and will then evolve to an ultimate capability of 130 metric tons. The SLS program marked a major milestone with the successful completion of the Critical Design Review in which detailed designs were reviewed and subsequently approved for proceeding with full-scale production. This marks the first time an exploration class vehicle has passed that major milestone since the Saturn V vehicle launched astronauts in the 1960s during the Apollo program. Each element of the vehicle now has flight hardware in production in support of the initial flight of the SLS - Exploration Mission-1 (EM-1), an uncrewed mission to orbit the moon and return, and progress in on track to meet the initial targeted launch date in 2018. In Utah and Mississippi, booster and engine testing are verifying upgrades made to proven shuttle hardware. At Michoud Assembly Facility (MAF) in Louisiana, the world's largest spacecraft welding tool is producing tanks for the SLS core stage. This paper will particularly focus on work taking place at Marshall Space Flight Center (MSFC) and United Launch Alliance (ULA) in Alabama, where upper stage and adapter elements of the vehicle are being constructed and tested. Providing the Orion crew capsule/launch vehicle interface and in-space propulsion via a cryogenic upper stage, the Spacecraft/Payload Integration and Evolution (SPIE) Element serves a key role in achieving SLS goals and objectives. The SPIE element marked a major milestone in 2014 with the first flight of original SLS hardware, the Orion Stage Adapter (OSA) which was used on Exploration Flight Test-1 with a design that will be used again on EM-1. Construction is already underway on the EM-1 Interim Cryogenic Propulsion Stage (ICPS), an in-space stage derived from the Delta Cryogenic Second Stage. Manufacture of the Orion Stage Adapter and the Launch Vehicle Stage Adapter is set to begin at the Friction Stir Facility located at MSFC while structural test articles are either completed (OSA) or nearing completion (Launch Vehicle Stage Adapter). An overview is provided of the launch vehicle capabilities, with a specific focus on SPIE Element qualification/testing progress, as well as efforts to provide access to deep space regions currently not available to the science community through a secondary payload capability utilizing CubeSat-class satellites.

SLS Navigation Model-Based Design Approach

NASA Technical Reports Server (NTRS)

Oliver, T. Emerson; Anzalone, Evan; Geohagan, Kevin; Bernard, Bill; Park, Thomas

2018-01-01

The SLS Program chose to implement a Model-based Design and Model-based Requirements approach for managing component design information and system requirements. This approach differs from previous large-scale design efforts at Marshall Space Flight Center where design documentation alone conveyed information required for vehicle design and analysis and where extensive requirements sets were used to scope and constrain the design. The SLS Navigation Team has been responsible for the Program-controlled Design Math Models (DMMs) which describe and represent the performance of the Inertial Navigation System (INS) and the Rate Gyro Assemblies (RGAs) used by Guidance, Navigation, and Controls (GN&C). The SLS Navigation Team is also responsible for the navigation algorithms. The navigation algorithms are delivered for implementation on the flight hardware as a DMM. For the SLS Block 1-B design, the additional GPS Receiver hardware is managed as a DMM at the vehicle design level. This paper provides a discussion of the processes and methods used to engineer, design, and coordinate engineering trades and performance assessments using SLS practices as applied to the GN&C system, with a particular focus on the Navigation components. These include composing system requirements, requirements verification, model development, model verification and validation, and modeling and analysis approaches. The Model-based Design and Requirements approach does not reduce the effort associated with the design process versus previous processes used at Marshall Space Flight Center. Instead, the approach takes advantage of overlap between the requirements development and management process, and the design and analysis process by efficiently combining the control (i.e. the requirement) and the design mechanisms. The design mechanism is the representation of the component behavior and performance in design and analysis tools. The focus in the early design process shifts from the development and management of design requirements to the development of usable models, model requirements, and model verification and validation efforts. The models themselves are represented in C/C++ code and accompanying data files. Under the idealized process, potential ambiguity in specification is reduced because the model must be implementable versus a requirement which is not necessarily subject to this constraint. Further, the models are shown to emulate the hardware during validation. For models developed by the Navigation Team, a common interface/standalone environment was developed. The common environment allows for easy implementation in design and analysis tools. Mechanisms such as unit test cases ensure implementation as the developer intended. The model verification and validation process provides a very high level of component design insight. The origin and implementation of the SLS variant of Model-based Design is described from the perspective of the SLS Navigation Team. The format of the models and the requirements are described. The Model-based Design approach has many benefits but is not without potential complications. Key lessons learned associated with the implementation of the Model Based Design approach and process from infancy to verification and certification are discussed

NASA's Space Launch System: A New Capability for Science and Exploration

NASA Technical Reports Server (NTRS)

Robinson, Kimberly F.; Creech, Stephen D.; May, Todd A.

2014-01-01

NASA's Marshall Space Flight Center (MSFC) is directing efforts to build the Space Launch System (SLS), a heavy-lift rocket that will launch the Orion Multi-Purpose Crew Vehicle (MPCV) and other high-priority payloads into deep space. Its evolvable architecture will allow NASA to begin with human missions beyond the Moon and then go on to transport astronauts or robots to distant places such as asteroids and Mars. Developed with the goals of safety, affordability, and sustainability in mind, SLS will start with 10 percent more thrust than the Saturn V rocket that launched astronauts to the Moon 40 years ago. From there it will evolve into the most powerful launch vehicle ever flown, via an upgrade approach that will provide building blocks for future space exploration. This paper will explain how NASA will execute this development within flat budgetary guidelines by using existing engines assets and heritage technology, from the initial 70 metric ton (t) lift capability through a block upgrade approach to an evolved 130-t capability, and will detail the progress that has already been made toward a first launch in 2017. This paper will also explore the requirements needed for human missions to deep-space destinations and for game-changing robotic science missions, and the capability of SLS to meet those requirements and enable those missions, along with the evolution strategy that will increase that capability. The International Space Exploration Coordination Group, representing 12 of the world's space agencies, has worked together to create the Global Exploration Roadmap, which outlines paths towards a human landing on Mars, beginning with capability-demonstrating missions to the Moon or an asteroid. The Roadmap and corresponding NASA research outline the requirements for reference missions for all three destinations. The SLS will offer a robust way to transport international crews and the air, water, food, and equipment they would need for extended trips to asteroids, the Moon, and Mars. SLS also offers substantial capability to support robotic science missions, offering benefits such as improved mass margins and radiation mitigation, and reduced mission durations. The SLS rocket, using significantly higher C3 energies, can more quickly and effectively take the mission directly to its destination, reducing trip time and cost. As this paper will explain, the SLS is making measurable progress toward becoming a global infrastructure asset for robotic and human scouts of all nations by providing the robust space launch capability to deliver sustainable solutions for advanced exploration.

NASA's Space Launch System: A New Capability for Science and Exploration

NASA Technical Reports Server (NTRS)

Crumbly, Christopher M.; May, Todd A.; Robinson, Kimberly F.

2014-01-01

The National Aeronautics and Space Administration's (NASA's) Marshall Space Flight Center (MSFC) is directing efforts to build the Space Launch System (SLS), a heavy-lift rocket that will launch the Orion Multi-Purpose Crew Vehicle (MPCV) and other high-priority payloads into deep space. Its evolvable architecture will allow NASA to begin with human missions beyond the Moon and then go on to transport astronauts or robots to distant places such as asteroids and Mars. Developed with the goals of safety, affordability, and sustainability in mind, SLS will start with 10 percent more thrust than the Saturn V rocket that launched astronauts to the Moon 40 years ago. From there it will evolve into the most powerful launch vehicle ever flown, via an upgrade approach that will provide building blocks for future space exploration. This paper will explain how NASA will execute this development within flat budgetary guidelines by using existing engines assets and heritage technology, from the initial 70 metric ton (t) lift capability through a block upgrade approach to an evolved 130-t capability, and will detail the progress that has already been made toward a first launch in 2017. This paper will also explore the requirements needed for human missions to deep-space destinations and for game-changing robotic science missions, and the capability of SLS to meet those requirements and enable those missions, along with the evolution strategy that will increase that capability. The International Space Exploration Coordination Group, representing 12 of the world's space agencies, has worked together to create the Global Exploration Roadmap, which outlines paths towards a human landing on Mars, beginning with capability-demonstrating missions to the Moon or an asteroid. The Roadmap and corresponding NASA research outline the requirements for reference missions for all three destinations. The SLS will offer a robust way to transport international crews and the air, water, food, and equipment they would need for extended trips to asteroids, the Moon, and Mars. SLS also offers substantial capability to support robotic science missions, offering benefits such as improved mass margins and radiation mitigation, and reduced mission durations. The SLS rocket, using significantly higher characteristic energy (C3), can more quickly and effectively take the mission directly to its destination, reducing trip time and cost. As this paper will explain, the SLS is making measurable progress toward becoming a global infrastructure asset for robotic and human scouts of all nations by providing the robust space launch capability to deliver sustainable solutions for advanced exploration.